nookie vs sexual intercourse

nookie and sexual intercourse both are nouns.

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

As nouns, sexual intercourse is a hypernym of nookie; that is, sexual intercourse is a word with a broader meaning than nookie:

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

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