100 Essential Hiking and Trekking Terms (Glossary)

Trail Types & Hiking Styles

• Day Hike – A hike short enough to be completed within a single day (no overnight camping).

• Backpacking – The activity of hiking while carrying all necessary gear (clothing, food, shelter) in a pack on your back, usually for multi-day trips.

• Trekking – A long, vigorous multi-day hike, often in wild or mountainous environments and sometimes off established trails.

• Thru-Hike – To hike a long-distance trail end-to-end in one continuous trip (typically within one hiking season).

• Section Hike – Completing a long-distance trail in separate segments rather than in one go (eventually covering the trail’s entire length over multiple trips).

• Loop Trail – A trail that starts and ends at the same location, forming a closed loop without retracing steps.

• Out-and-Back – A trail that leads to a specific endpoint (e.g. a summit or lake) where you turn around and hike back along the same route to the start.

• Slackpacking – A form of backpacking without carrying a full pack; typically, a hiker carries only a light daypack while someone else transports the heavier gear to the next stop.

• Peak Bagging – The activity of climbing a set list of mountain summits (often those above a certain height or in a particular range), “bagging” each peak as a achievement.

• Bushwalking – The Australian term for hiking in natural areas (equivalent to hiking/trekking/rambling in other regions).

• Tramping – New Zealand term for backpacking or hiking over rough country, typically involving multi-day trips with a backpack in the wilderness.

• Hillwalking – A British term for walking/hiking in hilly or mountainous terrain for leisure (similar to hiking, often used in the UK).

• Via Ferrata – Italian for “iron path”; a protected climbing route with fixed steel cables, rungs, and ladders affixed to rock faces, allowing hikers to traverse steep or exposed terrain securely.

• Hut-to-Hut – A style of multi-day trekking where instead of camping, hikers stay overnight in a series of huts or mountain lodges along the route.

Navigation & Terrain Terms

• Trailhead – The starting point of a trail, usually where a hike begins (often accessible by road and marked by signage).

• Trail Blaze – A marker (often a paint splash or tag) placed on trees, rocks, or posts to mark the path of a trail and guide hikers.

• Cairn – A human-made stack of stones used to mark a route or summit. Cairns are commonly found in open areas above treeline where trail blazes on trees aren’t possible.

• Switchback – A sharp zigzag turn in a trail on a steep slope, designed to gain elevation gradually. Switchback trails cut back and forth to ease the grade of ascent or descent.

• Topographic Map – A detailed map that represents three-dimensional terrain on a two-dimensional surface using contour lines to show elevation. It depicts land features (mountains, valleys, waterways) and helps with navigation.

• Contour Line – A line on a topographic map connecting points of equal elevation. Closely spaced contour lines indicate a steep slope, while widely spaced lines indicate gentle terrain.

• Elevation Gain – The total vertical distance ascended during a hike. For example, a trail starting at a valley and ending on a summit with a 1,000 m height difference has ~1,000 m of elevation gain (accumulated uphill).

• Treeline (Timberline) – The elevation on a mountain above which trees do not grow (due to cold or lack of moisture). Above the treeline, the landscape transitions to alpine tundra.

• Mountain Pass – A low point or gap in a mountain range that allows passage from one side to the other. Passes are often used as routes through otherwise rugged terrain.

• Col (Saddle) – The lowest point on a ridge between two peaks; essentially a minor mountain pass. Also called a saddle or notch, it’s a dip or depression along a ridgeline.

• Ridge – A long, narrow crest or elevated strip of land, often extending out from a mountain summit. Ridges connect peaks or ascend toward a summit, and hiking “the ridge” means following that high ground.

• Summit – The highest point of a hill or mountain; the mountain’s peak or topmost point. (Reaching the summit is usually the goal of an ascent.)

• Scree – A layer of small, loose rocks (gravel-sized) covering a slope, typically found at the base of cliffs or on mountainsides due to rockfall. Walking on scree can feel like walking on marbles.

• Talus – A slope or pile of larger rock debris (broken boulders) at the base of a cliff or steep slope. Talus pieces are bigger and more stable than scree, but still form a rough, rocky incline.

• Moraine – A ridge or mound of rocks and sediment deposited by a glacier. Moraines mark the glacier’s former edges or terminus; for example, a lateral moraine runs along the sides of a glacier’s path.

• Crevasse – A deep crack in a glacier or ice sheet. Crevasses can be meters wide and tens of meters deep, forming as the glacier’s ice moves and stretches. (They pose serious hazards to mountaineers on glaciers.)

• Whiteout – A weather condition in which snow (or fog/sand) causes visibility to be severely reduced. Horizon and landmarks disappear in a uniform whiteness, making navigation extremely difficult.

• False Summit – An optical illusion peak that appears to be the top of the mountain, but upon reaching it you discover a higher summit beyond. (False summits often trick tired climbers into thinking they’re done when they are not.)

• Fourteener (14er) – A mountain with a summit exceeding 14,000 feet (4,267 meters) in elevation. The term is commonly used in the U.S. (especially Colorado); “bagging a 14er” means climbing a peak over 14,000 ft high.

Hiking Techniques & Practices

• Bushwhacking – Traveling off-trail through dense vegetation, forcing your way through bushes, undergrowth, or forest where no clear path exists. (This often requires navigation skills and can be slow, strenuous travel.)

• Scrambling – Climbing up steep, rocky terrain using hands for balance and support, but generally without ropes. Scrambling is the intermediate between hiking and technical rock climbing.

• Glissade – A controlled slide down a snow slope, usually on the feet or sitting down, to quickly descend. In mountaineering, climbers glissade (often in a seated position) on soft snow as a quick way off a mountain.

• Self-Arrest – A technique used to stop an uncontrolled slide on a steep snow or ice slope, typically by using an ice axe. The climber drives the axe into the snow and uses body weight to halt a fall.

• Postholing – Sinking deeply into soft snow with each step, as if your legs are punching holes in the snow. “Postholing” often happens in late spring snow when hiking without snowshoes. (It’s exhausting and can be dangerous; snowshoes or skis prevent it.)

• Fording – Crossing a stream or river by walking through it. A safe ford is usually at a shallow section (a ford) with slow current and good footing. Hikers may need to unlink packs and use trekking poles for stability when fording rivers.

• Orienteering – Navigating with map and compass, often as a sport. Orienteering involves finding a series of checkpoints in unfamiliar terrain using only topographic maps and compass bearings.

• Route Finding – The skill of choosing a path through difficult or unmarked terrain. Good route finding involves identifying the safest and most efficient way forward, especially when no trail is visible (e.g. figuring out how to climb a boulder field or locate a pass).

• Ultralight Backpacking – A style of backpacking focused on minimizing pack weight. Ultralight hikers carefully reduce gear weight (often achieving a base weight under ~10–12 pounds) to travel faster and with less strain.

• Fastpacking – A hybrid of trail running and ultralight backpacking. Fastpackers jog or run on flatter sections and hike the uphills, carrying a very light pack to cover long distances quickly on multi-day trips.

• Dry Camp – A campsite where there is no water source available. Hikers must “dry camp” by carrying in all the water they need for the night and next morning. (It’s important to plan ahead for water when opting to dry camp.)

• Cache – A supply stash of food, water, or gear stored along a route for later use. Long-distance hikers sometimes leave a water cache in a desert section or mail themselves supply caches to remote locations on the trail.

Gear & Equipment

• Backpack – A large pack worn on the back, used by hikers to carry gear. Modern hiking backpacks have shoulder straps and a hip belt to distribute weight, and often internal frames for support.

• Daypack – A small backpack (typically ~10–30 liters capacity) used for day hikes. A daypack carries water, food, and essentials for a single day and is lighter/smaller than an overnight backpack.

• Tent – A portable shelter made of fabric (nylon or canvas) and poles. Hiking tents range from lightweight one-person tents to larger family tents, providing weather protection for overnight camping.

• Sleeping Bag – An insulated, zippered bag that a camper sleeps in for warmth at night. Sleeping bags are rated by temperature (e.g. a 0°C bag or a -10°C bag indicates the lowest comfort temperature) and filled with down or synthetic insulation.

• Sleeping Pad – A cushioned mat placed under a sleeping bag. It provides insulation from the cold ground and padding for comfort. Types include foam pads and inflatable air mats.

• Bivy Sack – A minimalist waterproof shelter that fits over a sleeping bag. A “bivy” (from bivouac sack) is essentially a small sack/tent just large enough for one person to sleep in, offering lightweight emergency shelter.

• Trekking Poles – Telescoping poles (used in pairs) that hikers hold for balance and support. Trekking poles help reduce stress on the knees during descents and improve stability on rough terrain by acting like a second pair of legs.

• Gaiters – Protective sleeves that cover the lower legs and top of boots. Gaiters keep mud, snow, and debris out of your boots and also provide extra water resistance in wet or snowy conditions (commonly used in snow or marshy hikes).

• Crampons – Traction devices with metal spikes that attach to boots for walking on ice and hard snow. Mountaineers use crampons to climb glaciers and icy slopes; the spikes bite into ice to prevent sliding.

• Microspikes – Light traction devices consisting of chains and small spikes (~¼–½ inch) that stretch over footwear. Hikers use microspikes on icy or packed snow trails (often on flatter terrain) for extra grip when full crampons are not needed.

• Snowshoes – Wide, flat frames attached to boots that allow walking on soft, deep snow by distributing weight (preventing postholing). Snowshoes essentially let you “float” on snow, making winter travel easier in powdery conditions.

• Ice Axe – A mountaineering tool with a pointed pick on one side of the head and a flat adze on the other, plus a spike at the handle’s end. Ice axes are used for support on steep snow, cutting steps, and self-arresting during a fall on icy slopes.

• Headlamp – A small, strap-mounted flashlight worn on the head. It provides hands-free light for hiking or camping in the dark. (Headlamps are part of the Ten Essentials and are critical for early starts, late finishes, or emergencies at night.)

• Water Filter – A portable filtration device that removes bacteria and protozoa from natural water sources, making the water safe to drink. Common types include pump filters, squeeze filters, and gravity filters. (Note: Viruses are smaller and require a purifier or chemical treatment.)

• Hydration Bladder – A flexible water reservoir (typically 1–3 liters) that sits in a backpack and connects to a drinking hose. Hydration bladders (e.g. CamelBak) allow hikers to sip water on the move via a bite valve, encouraging frequent hydration.

• Bear Canister – A hard-sided, bear-resistant container used to store food, trash, and scented items while camping. Many parks and trails require bear canisters in the backcountry to prevent bears from obtaining human food (which protects both hikers and wildlife).

• Bear Hang – A method of hanging food in a bag from a tree branch to keep it away from bears and other animals. A proper bear hang is suspended at least 10–15 feet off the ground and 4–6 feet out from the trunk. (Where bear canisters aren’t required, campers use bear hangs to protect their food.)

• GPS Device – A handheld or wearable Global Positioning System unit that uses satellites to determine your precise location coordinates. Hikers use GPS devices or GPS watches to navigate, mark waypoints, or follow pre-loaded routes, though they should carry a map and compass as backup.

• Compass – A navigation instrument with a magnetized needle that points toward magnetic north. Used with a map, a compass allows hikers to orient the map and take bearings to navigate when trails are unclear or nonexistent.

• Altimeter – A device that measures altitude (height above sea level). Many hiking watches have a barometric altimeter, which estimates elevation by air pressure. Knowing your altitude from an altimeter can help pinpoint your location on a topo map when navigating in mountains.

• Personal Locator Beacon (PLB) – A compact emergency device that, when activated, sends a distress signal (and GPS coordinates) via satellite to alert search and rescue authorities. PLBs (and satellite messengers) are carried for wilderness safety to summon help in life-threatening situations when no phone service is available.

• Backpacking Stove – A lightweight, portable stove for cooking on the trail. Common types are canister stoves (using pressurized gas canisters) and liquid-fuel stoves. These stoves allow hikers to boil water and prepare meals in the backcountry.

• Carabiner – A strong metal loop with a spring-loaded gate, used as a connector in climbing and also for clipping gear. Hikers might use carabiners to attach items to their pack. (In climbing, carabiners – often called “’biners” – are essential safety connectors.)

• Trail Runners – Lightweight trail-running shoes that many hikers use instead of boots. Trail runners are low-cut, breathable, and have grippy soles; they trade some ankle support and durability for lightness and comfort, and are favored by many long-distance backpackers for hiking long miles.

• Gore-Tex – A proprietary waterproof–breathable membrane used in outdoor gear (jackets, pants, boots). Material with Gore-Tex keeps rain out while allowing some sweat vapor to escape, helping hikers stay dry. (Many rain jackets are “Gore-Tex shells,” a key part of layering in bad weather.)

• Base Weight – The weight of a backpacker’s gear excluding consumables like food, water, and fuel. Base weight includes the pack and all equipment carried. Ultralight hikers strive for a very low base weight, since consumables will add additional load during the trip.

Safety & Survival Terms

• Hypothermia – A dangerously low core body temperature (below 35 °C or 95 °F). Hypothermia happens in cold, wet conditions when the body loses heat faster than it can produce it, leading to shivering, confusion, and loss of coordination – it is a life-threatening emergency if not treated (rewarming and sheltering the victim).

• Heat Exhaustion – A heat-related illness caused by loss of water and salt through excessive sweating and exposure to heat. Symptoms include heavy sweating, weakness, dizziness, nausea, and a rapid pulse. If not addressed (cool down, rehydrate), heat exhaustion can progress to heat stroke.

• Heat Stroke – A severe, life-threatening condition of overheating in which the body’s temperature regulation fails. Core temperature rises above ~40 °C (104 °F), and the person may stop sweating and become disoriented or unconscious. Heat stroke is a medical emergency requiring immediate cooling of the person and professional treatment.

• Dehydration – Excessive loss of bodily water, leading to symptoms like thirst, dry mouth, dizziness, and fatigue. In hiking, dehydration can result from not drinking enough fluids during exertion, especially in hot weather. Severe dehydration impairs performance and can cause heat illness, so hikers must drink water regularly and replace electrolytes on the trail.

• Altitude Sickness (AMS) – Also known as Acute Mountain Sickness, it’s a condition affecting some people at high altitudes (typically above ~2,500 m) due to lower oxygen levels. Symptoms include headache, nausea, fatigue, shortness of breath, and trouble sleeping. The primary treatment is to stop ascending and if necessary descend to lower altitude.

• Acclimatization – The process by which the body adapts to high altitude over time. Proper acclimatization (gained by ascending gradually and spending time at intermediate elevations) helps reduce altitude sickness. Techniques include “climb high, sleep low” and adding rest days so the body can produce more red blood cells and adjust to thinner air.

• HAPE – High Altitude Pulmonary Edema, a severe form of altitude illness where fluid accumulates in the lungs. It causes extreme shortness of breath, even at rest, coughing (sometimes with frothy sputum), and can be fatal. Descent and medical treatment (oxygen) are urgently required for HAPE.

• HACE – High Altitude Cerebral Edema, a critical altitude illness where the brain swells with fluid at high elevation. Symptoms include severe headache, confusion, loss of coordination (ataxia), and hallucinations. HACE is life-threatening – immediate descent and medical intervention are essential.

• Frostbite – Tissue damage that occurs when skin and underlying tissues actually freeze from extreme cold. Fingers, toes, nose, and ears are most at risk. Early signs include numbness and a pale appearance of the skin; severe frostbite can cause permanent injury. Prevented by proper cold-weather gear and avoiding prolonged exposure.

• Avalanche – A large mass of snow sliding rapidly down a mountainside. Avalanches can be triggered by new snow, warming temperatures, or humans on unstable snowpacks. Winter backcountry travelers carry avalanche safety gear (beacon, shovel, probe) and assess snow conditions to avoid avalanche-prone slopes.

• Bear Spray – A canister of pepper spray formulated for deterring aggressive bears. In an encounter, one would spray a cloud toward the charging bear; the capsaicin irritant can cause the bear to retreat. Hikers in bear country (e.g. grizzly habitat) often carry bear spray as a safety measure.

• Potable Water – Water that is safe to drink. In the backcountry, “potable water” usually means water that has been treated (filtered, boiled, or chemically purified) to remove harmful microorganisms. Clear running streams are not always potable without treatment.

• Ten Essentials – A list of ten essential emergency/survival items that hikers should carry on any backcountry outing. The classic Ten Essentials are: Navigation (map & compass), Headlamp, Sun Protection (sunscreen, sunglasses), First Aid kit, Knife (and repair kit), Fire (matches/lighter), Shelter (emergency bivy or tarp), Extra Food, Extra Water, and Extra Clothing. These items help one stay safe if an unexpected night out or emergency occurs.

Environmental & Ethics Terms

• Leave No Trace (LNT) – A set of outdoor ethics promoting conservation and minimal human impact on the environment. The 7 Principles of Leave No Trace include planning ahead, traveling and camping on durable surfaces, proper waste disposal, leaving what you find, minimizing campfire impact, respecting wildlife, and being considerate of others. Hikers follow LNT guidelines to keep wilderness areas pristine.

• Pack It In, Pack It Out – A core Leave No Trace practice meaning whatever you carry into the wilderness (trash, gear, waste), you must carry back out. In short: do not leave garbage or belongings behind. If you packed it in, pack it out with you. (This keeps campsites and trails free of litter.)

• Backcountry – Remote, undeveloped areas where hikers travel typically by trails and do not have nearby road access. Backcountry areas often require self-sufficiency and permits; amenities like treated water or toilets are usually absent. (In National Parks, “backcountry” generally means an area more than a certain distance from a trailhead or road.)

• Frontcountry – The more developed, accessible parts of parks or natural areas, usually near roads or trailheads. Frontcountry sites include campgrounds, picnic areas, and short nature trails – places where beginners or day-visitors can easily go. It’s essentially the opposite of backcountry.

• Wild Camping – Camping outside of designated campgrounds, in a dispersed fashion, typically on public land. Also known as “dispersed camping,” this is common in many countries (called wild camping particularly in the UK/Europe) where one finds a legal, low-impact spot to camp in the wilderness with no facilities. It requires following rules (like distance from water sources) and LNT principles.

• Cryptobiotic Soil – Also called biological soil crust, it’s a fragile living crust of organisms (cyanobacteria, lichens, mosses) on top of soil in some desert environments. It stabilizes soil from erosion and retains moisture. Hikers must avoid stepping on cryptobiotic soil (often the blackish crusts in deserts) because one footstep can destroy decades of growth, leading to erosion.

Slang & Trail Community Jargon

• Trail Magic – Serendipitous acts of kindness that hikers encounter on the trail. Examples of trail magic include finding a cooler of cold drinks at a road crossing, free meals provided by volunteers, or getting an unexpected ride into town. Trail magic brings welcome relief and morale boosts to long-distance hikers.

• Trail Angel – A person who provides trail magic or help to hikers out of kindness. Trail angels might leave water caches in dry areas, host hikers in their home, give free rides, or set up food feeds along the trail. They are beloved figures in the hiking community.

• Trail Name – A nickname adopted by or given to a hiker on a long trail. Especially common on trails like the Appalachian Trail, many thru-hikers go by trail names (alter egos) instead of their real names. It’s an informal tradition that builds camaraderie (e.g. “Crawler,” “Sunrise,” or “Wrong Way” as trail names).

• Zero Day – A rest day during a long-distance hike in which zero miles are covered. Hikers take “zeros” typically in trail towns or base camps to recuperate – doing laundry, showering, eating big meals, and giving their bodies a break. (Contrast with a “nero.”)

• Nero – Short for “nearly zero” day. This is a very low-mileage day on a long trail – perhaps hiking just a few miles (for example, to enter a town or reach a shelter) and resting the remainder. Hikers might do a nero when they get into a town in the afternoon, having hiked only a short distance that day.

• Hike Your Own Hike (HYOH) – A popular motto in the hiking community, meaning each person should hike in the way that suits them best. It’s an encouragement to not judge others’ styles or feel pressured to conform – whether one hikes fast or slow, carries this or that gear, it’s all about personal choice and enjoyment.

• Hiker Hunger – The insatiable appetite that kicks in for many long-distance hikers after a few weeks on trail. Due to constant high calorie burn, thru-hikers develop “hiker hunger” and can eat enormous quantities of food (and still lose weight). Town stops are often marked by feasting to satisfy hiker hunger.

• Yo-yo – In a thru-hiking context, to “yo-yo” a trail means to complete a trail end-to-end in one direction and then turn around and thru-hike it back in the opposite direction. For example, finishing the Pacific Crest Trail in Canada and then immediately hiking back to Mexico. A hiker who does this is sometimes called a “yo-yo” hiker of that trail.

• Triple Crown – In American long-distance hiking, this refers to completing the three major national scenic trails: the Appalachian Trail (~2,190 miles), the Pacific Crest Trail (~2,650 miles), and the Continental Divide Trail (~3,100 miles). A “Triple Crowner” is someone who has thru-hiked all three.

• Camel Up – Slang for drinking a large amount of water at a water source to fully hydrate before leaving, especially when about to enter a dry section. Hikers “camel up” at a stream or spring (drink to capacity) so they don’t have to carry as much water in their pack. This term likens hikers to camels storing water.