- that touches; touching
- Geom. touching and not intersecting a curve or curved surface at one and only one point: said of a line or plane

Origin of tangent

Classical Latin*tangens*, present participle of

*tangere*, to touch: see tact

- Geom.
- a tangent line, curve, or surface
- the length of a straight line tangent to a curve, measured from the point of tangency to the intersection of the tangent line with the x-axis

- Trigonometry the reciprocal of the cotangent; specif.,
- the ratio of the opposite side of a given acute angle in a right triangle to the adjacent side
- an equivalent, positive or negative ratio for certain related angles (Ex.: the tangent of 57° or 237° is 1.5399, of 123° or 303° is ?1.5399) or real numbers representing radians (Ex.: the tangent of .9948 radians (57°) is 1.5399)

Origin of tangent

< ModL (*linea) tangens*, tangent (line)

**tangent Idioms**

go off at a tangent