tangent

C2 Topic:Space, Position & Direction

US /ˈtæn.d͡ʒənt/ See IPA manual

Freq #41199

Meanings

1

noun
a ratio of the opposite to the adjacent side of a right-angled triangle

I used the tangent of the sides to calculate the length of the hypotenuse.
2

noun
a straight line or plane that touches a curve or curved surface at a point but does not intersect it at that point

The tangent touched the arc at its apex.
3

noun
a topic that is related, but not the same as, an original topic

I was told to talk about boats, but I went on a tangent about trade winds.

Thesaurus

Synonyms

digression excursus

Opposites

secant

Word family

Forms tangents

Derived forms arctangentcotangenttangently

Related forms cosine sine tangentialtrigonometrycontiguous

Appears in

Phrases (1)

See all

tangent plane
a plane containing the tangent lines through a particular point on a surface

Noun + noun

Simplified etymology

Tangent comes from Latin tangere, “to touch.” It entered English in the late sixteenth century and was first used in geometry to mean “touching.”

Etymology

Borrowed from Latin tangentem, the accusative of tangēns (“touching”) (in the phrase līnea tangēns (“a touching line”)), the present participle of the verb tangō (“touch”, verb), from Proto-Italic *tangō, from Proto-Indo-European *teh₂g- (“to touch”). Cognate with Old English þaccian (“to touch lightly, pat, stroke”). More at thack, thwack.

*teh₂g- Proto-Indo-European tangentem Latin *tangō Proto-Italic

View etymology graph ->

Topics

Space, Position & Direction Word Formation & Derivatives

External links

# tangent

**Type:** Word
**Level:** C2
**Part of speech:** noun
**IPA (US):** /ˈtæn.d͡ʒənt/
**Frequency rank:** 41199

## Meanings
1. a ratio of the opposite to the adjacent side of a right-angled triangle
2. a straight line or plane that touches a curve or curved surface at a point but does not intersect it at that point
3. a topic that is related, but not the same as, an original topic

## Examples
- I used the tangent of the sides to calculate the length of the hypotenuse.
- The tangent touched the arc at its apex.
- I was told to talk about boats, but I went on a tangent about trade winds.

## Synonyms
- digression
- excursus

## Antonyms
- secant

## Derived Forms
- arctangent
- cotangent
- tangently

## Related Forms
- cosine
- sine
- tangential
- trigonometry
- contiguous

## Roots and Affixes
- Root: *teh₂g-
- Root: tangentem
- Root: *tangō

## Etymology
Borrowed from Latin tangentem, the accusative of tangēns (“touching”) (in the phrase līnea tangēns (“a touching line”)), the present participle of the verb tangō (“touch”, verb), from Proto-Italic *tangō, from Proto-Indo-European *teh₂g- (“to touch”). Cognate with Old English þaccian (“to touch lightly, pat, stroke”). More at thack, thwack.

## Topics
- Space, Position & Direction
- Word Formation & Derivatives

markdown