Humbug of the rasher kind? (6)

I believe the answer is:

gammon

I'm a little stuck... Click here to teach me more about this clue!

'humbug' is the definition.
(thesaurus)

I don't understand how the remainder of the clue works.

(Other definitions for gammon that I've seen before include "Hind portion of a side of bacon" , "Cured meat of hindquarters of a pig" , "bit of a swine" , "Smoked pig meat" , "Hoax - hock of hog" .)

I've seen this clue in the Evening Standard.

Want a hint initially instead of a full solution? Install my app