coitus vs carnal knowledge

coitus and carnal knowledge both are nouns.

Word	Noun	Adjective	Verb	Adverb
coitus	Yes	No	No	No
carnal knowledge	Yes	No	No	No

As nouns, coitus and carnal knowledge are synonyms defined as:

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

coitus (noun)	carnal knowledge (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