arctan vs arctangent

arctan and arctangent both are nouns.

Word	Noun	Adjective	Verb	Adverb
arctan	Yes	No	No	No
arctangent	Yes	No	No	No

As nouns, arctan and arctangent are synonyms defined as:

arctan and arctangent: the inverse function of the tangent; the angle that has a tangent equal to a given number

Other synonyms of arctan include arc tangent, inverse tangent.

arctan (noun)	arctangent (noun)
the inverse function of the tangent; the angle that has a tangent equal to a given number	the inverse function of the tangent; the angle that has a tangent equal to a given number