snogging vs cuddling

snogging and cuddling both are nouns.

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

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

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

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

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