arcsine arcsin • arc sine · · · Info · Definitions · Synonyms · Characters · · arcsine · · Text Latin · · Script 7 · · Length 2 · · Syllables Definitions · · · (noun) the inverse function of the sine; the angle that has a sine equal to a given number. Synonyms: arc sine, arcsin, inverse sine. · · Noun Definition 1 Synonyms · · · arc sine · · Synonym 1 arcsin · · Synonym 2 inverse sine · · Synonym 3 Characters · · a latin small letter a U+0061 c latin small letter c U+0063 e latin small letter e U+0065 i latin small letter i U+0069 n latin small letter n U+006E r latin small letter r U+0072 s latin small letter s U+0073