Plastic surgeon injected with cold sponge (8)
I believe the answer is:
scrounge
'sponge' is the definition.
(I've seen this before)
'plastic surgeon injected with cold' is the wordplay.
'plastic' indicates anagramming the letters (plastic can mean easily moulded).
'injected with' is an insertion indicator.
'cold' becomes 'c' (eg on taps).
'surgeon' with letters rearranged gives 'srounge'.
'srounge' placed around 'c' is 'SCROUNGE'.
(Other definitions for scrounge that I've seen before include "Seek something free from others" , "Obtain (something) for free" , "bum" , "Cur's gone (anag) - beg" , "Obtain by begging" .)