steep

Steep is an adjective used to describe a surface or terrain that rises sharply relative to a horizontal plane. A steep slope, roof, or cliff has a large incline, making ascent or descent more difficult and sometimes hazardous. The term is commonly used in everyday language as well as in engineering, construction, and outdoor activities.

Geometrically and in civil engineering, steepness is the magnitude of the slope. It can be expressed as a gradient (rise over run), an angle of inclination, or a percent grade. The angle θ relates to slope by tan θ = |slope|. Percent grade is 100 times rise over run; for example, a 10% grade or a 30-degree slope conveys a steep incline. Steepness affects stability, drainage, erosion, and accessibility; steeper sections of roads or trails may require switchbacks, extra braking, or alternate routes.

Common contexts include: road design, where steeper grades influence vehicle performance and safety; hiking and mountaineering, where steep terrain impacts pace and risk; and architecture, where roof pitch determines drainage and wind resistance. In geology, steep slopes are more prone to landslides and rockfalls, especially when destabilized by weather or human activity.

As a verb, steep means to soak or immerse in a liquid to extract flavors or soften materials, as in steeping tea or herbs. It can also be used figuratively to indicate something deeply imbued or saturated, such as being steeped in tradition.