Like Rambo's coat - hot, with zip (5)
I believe the answer is:
macho
'like rambo's' is the definition.
(I've seen this in another clue)
'coat hot with zip' is the wordplay.
'coat' becomes 'mac' (mac is a kind of coat).
'hot' becomes 'h' (abbreviation, eg on taps).
'with' means one lot of letters go next to another.
'zip' becomes 'o' (zip can mean zero).
'mac'+'h'+'o'='MACHO'
(Other definitions for macho that I've seen before include "Ramboesque" , "Ultra-masculine" , "Blokeish" , "Typically tough (guy)" , "Like aggressive male" .)