arc sine vs arcsine

arc sine and arcsine both are nouns.

Word	Noun	Adjective	Verb	Adverb
arc sine	Yes	No	No	No
arcsine	Yes	No	No	No

As nouns, arc sine and arcsine are synonyms defined as:

arc sine and arcsine: the inverse function of the sine; the angle that has a sine equal to a given number

Other synonyms of arc sine include arcsin, inverse sine.

arc sine (noun)	arcsine (noun)
the inverse function of the sine; the angle that has a sine equal to a given number	the inverse function of the sine; the angle that has a sine equal to a given number