caressing vs necking

caressing and necking both are nouns.

Word	Noun	Adjective	Verb	Adverb
caressing	Yes	No	No	No
necking	Yes	No	No	No

As nouns, caressing and necking are synonyms defined as:

caressing and necking: affectionate play (or foreplay without contact with the genital organs)

Other synonyms of caressing include cuddling, fondling, hugging, kissing, petting, smooching, snuggling.

caressing (noun)	necking (noun)
affectionate play (or foreplay without contact with the genital organs)	affectionate play (or foreplay without contact with the genital organs)
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