arcsine vs arc sine

arcsine and arc sine both are nouns.

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

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

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

Other synonyms of arcsine include arcsin, inverse sine.

arcsine (noun)	arc sine (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