# tangent

## English

Wikipedia has an article on:

Wikipedia

A straight line tangent to a curve
Tangent function of unit circle

### Etymology

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-Indo-European *tag-, *taǵ- (to touch). Cognate with Old English þaccian (to touch lightly, pat, stroke). More at thack, thwack.

### Noun

tangent (plural tangents)

1. (geometry) A straight line touching a curve at a single point without crossing it there.
2. (trigonometry) In a right triangle, the ratio of the length of the side opposite the angle to the length of the side adjacent to the angle. Symbols: tan, tg
3. A topic nearly unrelated to the main topic, but having a point in common with it.
I believe we went off onto a tangent when we started talking about monkeys on unicycles at his retirement party.
• 1928, Lawrence R. Bourne, chapter 1, Well Tackled![1]:
“Uncle Barnaby was always father and mother to me,” Benson broke in; then after a pause his mind flew off at a tangent. “Is old Hannah all right—in the will, I mean?”
• 2009: Stuart Heritage, Hecklerspray, Friday the 22nd of May in 2009 at 1 o’clock p.m., “Jon & Kate Latest: People You Don’t Know Do Crap You Don’t Care About
Jon & Kate Plus 8 is a show based on two facts: (1) Jon and Kate Gosselin have eight children, and (2) the word ‘Kate’ rhymes with the word ‘eight’. One suspects that if Kate were ever to have another child, a shady network executive would urge her to put it in a binbag with a brick and drop it down a well. But this is just a horrifying tangent.
4. A small metal blade by which a clavichord produces sound.

#### Translations

The translations below need to be checked and inserted above into the appropriate translation tables, removing any numbers. Numbers do not necessarily match those in definitions. See instructions at Help:How to check translations.

tangent (not comparable)

1. (geometry) Touching a curve at a single point but not crossing it at that point.
2. Of a topic, only loosely related to a main topic.