coitus vs sexual intercourse

coitus and sexual intercourse both are nouns.

Word	Noun	Adjective	Verb	Adverb
coitus	Yes	No	No	No
sexual intercourse	Yes	No	No	No

As nouns, coitus and sexual intercourse are synonyms defined as:

coitus and sexual intercourse: sexual activity between individuals, especially the insertion of a man's penis into a woman's vagina until orgasm and ejaculation occur

coitus (noun)	sexual intercourse (noun)
sexual activity between individuals, especially the insertion of a man's penis into a woman's vagina until orgasm and ejaculation occur	sexual activity between individuals, especially the insertion of a man's penis into a woman's vagina until orgasm and ejaculation occur