Standard Lemma guide

arccosine

noun · 2 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

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No pronunciation record was provided for this word.

1

noun

Meaning 1

Any of several single-valued or multivalued functions that are inverses of the cosine function.

Definition source: English Wiktionary via Wiktextract

Topics: mathematics, sciences, trigonometry

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

noun

Meaning 2

the inverse function of the cosine; the angle that has a cosine equal to a given number

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: arc cosine, arccos, inverse cosine

Antonyms: none provided

Broader terms: trigonometric function, circular function

History

Etymology

Etymology tree Proto-Indo-European *h2erkw- Proto-Indo-European *h2erkwos Proto-Italic *arkuos Latin arcusder. English arc- Proto-Indo-European *ḱe? Proto-Indo-European *ḱóm Proto-Italic *kom Proto-Italic *kom- Latin con- Latin co-der. English co- Proto-Indo-European *sinos Proto-Italic *sinus Latin sinusbor. English sine English cosine English arccosine From arc- + cosine.

Across languages

Translations

19 source translations are retained for this English entry.

  • Asturian: arcocosenu — inverse of the cosine function
  • Catalan: arccosinus — inverse of the cosine function
  • Chinese Mandarin: 反餘弦 /反余弦 (fǎnyúxián) — inverse of the cosine function
  • Czech: arkuskosinus — inverse of the cosine function
  • Dutch: arccosinus — inverse of the cosine function
  • Finnish: arkuskosini — inverse of the cosine function
  • French: arc cosinus — inverse of the cosine function
  • Galician: arco coseno — inverse of the cosine function
  • German: Arkuskosinus — inverse of the cosine function
  • Hungarian: arkuszkoszinusz — inverse of the cosine function
  • Italian: arcocoseno — inverse of the cosine function
  • Japanese: アークコサイン (ākukosain) — inverse of the cosine function
  • Khmer: អាកកូស៊ីនុស (ʼaakkousiinuh) — inverse of the cosine function
  • Korean: 아크코사인 (akeukosain) — inverse of the cosine function
  • Māori: whenu kōaro — inverse of the cosine function
  • Portuguese: arco cosseno — inverse of the cosine function
  • Romanian: arccosinus — inverse of the cosine function
  • Russian: аркко́синус (arkkósinus) — inverse of the cosine function
  • Spanish: arcocoseno — inverse of the cosine function