Firedog put together with press (7)
I believe the answer is:
andiron
'firedog' is the definition.
(synonyms)
'put together with press' is the wordplay.
'put together' means one lot of letters go next to another.
'with' becomes 'and'.
'press' becomes 'iron' (ironing is a kind of pressing).
'and' put next to 'iron' is 'ANDIRON'.
(Other definitions for andiron that I've seen before include "bar near fire" , "Fireplace log supporter" , "Firedog -- Odin ran (anag)" , "one of two keeping fire going" , "Dog" .)