X vs sexual activity

X and sexual activity both are nouns.

Word	Noun	Adjective	Verb	Adverb
X	Yes	No	No	No
sexual activity	Yes	No	No	No

X (noun)	sexual activity (noun)
street names for methylenedioxymethamphetamine	activities associated with sexual intercourse
the 24th letter of the Roman alphabet
the cardinal number that is the sum of nine and one; the base of the decimal system