incline

Incline is a term with several related meanings. As a noun, it denotes a surface that rises from a lower to a higher point—a slope, hill, or ramp. A road’s steepness or grade is described by its incline. As a verb, incline means to tilt or bend something or to lean toward something (for example, to incline one’s head) or to begin to favor a particular view or course of action.

Measurement and calculations: An incline is described by its angle or its grade. The grade is the rise divided by the run, often expressed as a percentage. The angle relates to grade by trigonometric relations (tan θ = rise/run). In engineering, the incline plane is a classic simple machine that reduces the effort required to raise a load; ideal mechanical advantage equals the length of the plane divided by the height, with friction affecting real performance. Ramps and access paths use specific maximum slopes for safety and usability.

Other uses: In astronomy, inclination is the angle between an orbit’s plane and a reference plane, such as the ecliptic or celestial equator. In geology and surveying, inclination (or tilt) describes the orientation of rocks and strata relative to horizontal, often measured with a clinometer or similar instrument. The term inclination also appears in ordinary language as a synonym for tendency or preference.

Etymology and notes: Incline comes from Latin inclinare, meaning to bend or tilt. Related forms include incline (to tilt) and inclination (a tendency). The word’s senses cover physical tilting, geometric slope, and figurative predisposition, illustrating its broad applicability across science and everyday speech.