BASE jumping involves jumping from fixed structures (Buildings), antennas, spans (Bridges), and natural Earth features like cliffs or mountains.

Technical climbing refers to mountaineering ascents that require specialized equipment and techniques to overcome challenging terrain, including rock faces, ice, and mixed conditions.

In whitewater rafting, Class VI rapids represent the most extreme level of difficulty, characterized by violent currents, large waves, and hazardous obstacles that require expert skills and specialized equipment to navigate safely.

In surfing, a barrel is a large, hollow wave that breaks with great force, creating a tube-like shape that skilled surfers can ride inside, performing maneuvers and experiencing the thrill of the wave's power.

In skydiving, a twister is a freefall maneuver where the skydiver rotates their body rapidly around their vertical axis, creating a spinning motion while maintaining a stable position.

In rock climbing, an overhang is a section of a climb where the rock face is angled steeply downward, requiring climbers to use specialized techniques and equipment, such as ropes, harnesses, and cams, to ascend safely.

In skiing, powder skis are specialized skis designed for off-trail skiing in deep powder snow. They are typically wider and have a rockered shape, allowing skiers to float on top of the snow and maneuver easily through challenging terrain.

In kayaking, an Eskimo roll is a maneuver where the kayaker flips their kayak upside down and then rolls it back upright using their paddle and body movements. It is a fundamental skill for kayakers to recover from capsizes and continue paddling safely.

In mountain biking, a downhill trail is a challenging section of a trail that involves steep drops, jumps, and technical obstacles. It requires riders to have excellent bike handling skills and the ability to navigate difficult terrain at high speeds.

In paragliding, a cross-country glider is a specialized type of paraglider designed for high-altitude flights and long-distance soaring. It has a high aspect ratio and a lightweight construction, allowing pilots to cover long distances and explore vast landscapes.

In spelunking, a chasm is a deep, vertical shaft or pit in a cave system. It is a natural feature formed by the erosion of rock over time and can be a challenging obstacle for cavers to navigate.

In whitewater kayaking, a whitewater kayak is a specialized type of kayak designed for navigating extreme rapids and waterfalls. It has a closed deck, a reinforced hull, and specialized features that allow kayakers to maneuver safely through challenging whitewater conditions.

In mountaineering, a high camp is a camp established at a high elevation on a mountain, often used as a base for climbers to acclimatize and prepare for the summit. It is typically located above the base camp and serves as a staging point for the final ascent.

In rock climbing, a crack climb is a climbing route that follows a natural crack or fissure in the rock. Crack climbers use specialized techniques and equipment, such as cams and nuts, to protect themselves as they ascend the crack.

In skiing, racing skis are specialized skis designed for high-speed racing on groomed slopes. They are typically longer and narrower than other types of skis, and they have a stiff flex pattern that provides stability and control at high speeds.