# Definition of 'tangent'

noun

1.

2.

(of an angle) a trigonometric function that in a right-angled triangle is the ratio of the length of the opposite side to that of the adjacent side; the ratio of sine to cosine

. Abbreviation: tan4. music

5. on a tangent

adjective

7.

touching

8.

Collins English Dictionary. Copyright © HarperCollins Publishers

## Derived forms

tangency (ˈtangency) noun

## Word origin of 'tangent'

C16: from Latin phrase līnea tangēns the touching line, from tangere to touch adjective

1.

that touches; touching

2. Geometry

touching and not intersecting a curve or curved surface at one and only one point

said of a line or plane
noun

3. Geometry

a.

a tangent line, curve, or surface

b.

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

4. Trigonometry
Mathematics

the reciprocal of the cotangent

; specif.,
b.

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)

SIMILAR WORDS: adˈjacent

**Idioms:**

Webster’s New World College Dictionary, 4th Edition. Copyright © 2010 by
Houghton Mifflin Harcourt. All rights reserved.

## Derived forms

tangency (ˈtangency) noun

## Trends of 'tangent'

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