But one's honoured companion is macho! (5)
I believe the answer is:
butch
'is macho' is the definition.
(synonyms)
'but one's honoured companion' is the wordplay.
I cannot really see how this works, but
'companion' could be 'ch' (Companion of Honour) and 'ch' is located in the answer.
The remaining letters 'but' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for butch that I've seen before include "Aggressively masculine" , "Macho" , "Tough" , "Acting as a male (colloq.)" , "Markedly masculine" .)