snogging vs necking

snogging and necking both are nouns.

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

As nouns, necking is a hypernym of snogging; that is, necking is a word with a broader meaning than snogging:

snogging: (British informal) cuddle and kiss
necking: affectionate play (or foreplay without contact with the genital organs)

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

snogging (noun)	necking (noun)
(British informal) cuddle and kiss	affectionate play (or foreplay without contact with the genital organs)
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