Klutz left masseur without top (6)
I believe the answer is:
lubber
'klutz' is the definition.
(synonyms)
'left masseur without top' is the wordplay.
'left' becomes 'l' (common abbreviation).
'masseur' becomes 'rubber' (a masseur rubs someone's body).
'without top' means to remove the first letter.
'rubber' with its initial letter taken off is 'ubber'.
'l'+'ubber'='LUBBER'
(Other definitions for lubber that I've seen before include "A clumsy fellow, usually with land" , "No salt" , "Clumsy type" .)