necking vs sexual practice

necking and sexual practice both are nouns.

Word	Noun	Adjective	Verb	Adverb
necking	Yes	No	No	No
sexual practice	Yes	No	No	No

necking (noun)	sexual practice (noun)
affectionate play (or foreplay without contact with the genital organs)	activities associated with sexual intercourse
the molding at the top of a column