Having a man around would spoil it (3)
I believe the answer is:
mar
'it' is the definition.
The definition suggests a singular noun which matches the answer.
'having a man around would spoil' is the wordplay.
I cannot quite understand how this works, but
'a' is found in the answer.
'man' could be 'mr' (Mr is an example) and 'mr' is present in the remaining letters.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for mar that I've seen before include "Oh dear!" , "Spoil or deface" , "Ruin" , "when spring growth starts?" , "wreck" .)