Neck and part of cheek is snogged (4)
I believe the answer is:
kiss
'neck' is the definition.
(kissing is a kind of necking)
'part of cheek is snogged' is the wordplay.
'part of' says the answer is hidden in the clue.
'KISS' is hidden within 'cheek is snogged'.
'and' is the link.
(Other definitions for kiss that I've seen before include "Expression of love" , "Buss" , "Neck - peck" , "Eg, smacker, peck" , "x (that may be French)" .)