tangent

1 of 2

noun

tan·​gent ˈtan-jənt 

1

: an abrupt change of course : digression

the speaker went off on a tangent

2

a

: the trigonometric function that for an acute angle is the ratio between the leg opposite to the angle when it is considered part of a right triangle and the leg adjacent

b

: a trigonometric function that is equal to the sine divided by the cosine for all real numbers θ for which the cosine is not equal to zero and is exactly equal to the tangent of an angle of measure θ in radians

3

: a line that is tangent

specifically : a straight line that is the limiting position of a secant of a curve through a fixed point and a variable point on the curve as the variable point approaches the fixed point

4

: a small upright flat-ended metal pin at the inner end of a clavichord key that strikes the string to produce the tone

tangent

2 of 2

adjective

1

a

: meeting a curve or surface in a single point if a sufficiently small interval is considered

straight line tangent to a curve

b(1)

: having a common tangent line at a point

tangent curves

(2)

: having a common tangent plane at a point

tangent surfaces

2

: diverging from an original purpose or course : irrelevant

tangent remarks

Synonyms

Noun

• aside
• digression
• divagation
• excursion

Examples of tangent in a Sentence

Noun

in the middle of her description of her dog's symptoms, she went off on a tangent about its cute behavior

Recent Examples on the Web

Noun

Odd tangents by Trump, such as about the fictional cannibal Hannibal Lecter or the late golfer Arnold Palmer’s genitalia, have also become routine. —Kevin Rector, Los Angeles Times, 2 Nov. 2024

Stephen seemed to have a couple tangents like that one. —Laura Bradley, Vulture, 10 Oct. 2024

Adjective

By 1643, René Descartes had discovered a simple relationship between the curvatures of any four circles that are tangent to each other. —Quanta Magazine, 10 Aug. 2023

That leaves us with the tangent function. —Rhett Allain, Wired, 14 Mar. 2022

Word History

Etymology

Noun

New Latin tangent-, tangens, from linea tangens tangent line

Adjective

Latin tangent-, tangens, present participle of tangere to touch; perhaps akin to Old English thaccian to touch gently, stroke

First Known Use

Noun

1594, in the meaning defined at sense 2a

Adjective

1594, in the meaning defined at sense 1a

Phrases Containing tangent

• arc tangent
• go off on a tangent
• tangent plane

Kids Definition

tangent

1 of 2 adjective

tan·​gent ˈtan-jənt 

: touching a curve or surface at only one point

a straight line tangent to a circle

tangent

2 of 2 noun

1

: a trigonometric function that for an acute angle in a right triangle is the ratio of the side opposite the angle to the side next to it

2

: a line that is tangent

3

: a sudden change of course

the speaker went off on a tangent

tangential

tan-ˈjen-chəl

adjective

tangentially

-ˈjench-(ə-)lē

adverb

Etymology

Adjective

from Latin tangent-, tangens "touching," from tangere "to touch" — related to contact, tactile, tangible