sexual intercourse vs intercourse

sexual intercourse and intercourse both are nouns.

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

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

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

Other synonyms of sexual intercourse include carnal knowledge, coition, coitus, copulation, relation, sex act, sexual congress, sexual relation.

sexual intercourse (noun)	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
	communication between individuals