noun ·Uncommon ·Advanced level

Definitions

Noun

1. 1
   In a right triangle, the ratio of the length of the side adjacent to an acute angle to the length of the hypotenuse. Symbol: cos
2. 2
   ratio of the adjacent side to the hypotenuse of a right-angled triangle wordnet

Synonyms

All synonyms

argumentcoscosinuselementequationformula

Example

More examples

"The functions sine and cosine take values between -1 and 1 (-1 and 1 included)."

Etymology

From co- + sine, short for complementi sinus in Latin, meaning “sine of the complement”. Doublet of cosinus.

Related phrases

Fourier cosine seriesLambert's cosine lawcosine curvecosine formulacosine lawcosine rulecoversed cosinehyperbolic cosineinverse cosineversed cosinepower seriesright triangle

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.