copulation vs sexual intercourse

copulation and sexual intercourse both are nouns.

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

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

copulation 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

copulation (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