variants or arccosine
plural arc cosines or arccosines
: the inverse function of the cosine
if y is the cosine of θ, then θ is the arccosine of y
abbreviation arccos

Word History

First Known Use

circa 1884, in the meaning defined above

Time Traveler
The first known use of arc cosine was circa 1884

Dictionary Entries Near arc cosine

Cite this Entry

“Arc cosine.” Dictionary, Merriam-Webster, Accessed 6 Dec. 2022.

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