cotangent vs cotan

cotangent and cotan both are nouns.

Word	Noun	Adjective	Verb	Adverb
cotangent	Yes	No	No	No
cotan	Yes	No	No	No

As nouns, cotangent and cotan are synonyms defined as:

cotangent and cotan: ratio of the adjacent to the opposite side of a right-angled triangle

cotangent (noun)	cotan (noun)
ratio of the adjacent to the opposite side of a right-angled triangle	ratio of the adjacent to the opposite side of a right-angled triangle