Mediocre temp initially standing in for female domestic (8)
I believe the answer is:
interior
'domestic' is the definition.
(similar in meaning)
'mediocre temp initially standing in for female' is the wordplay.
I cannot really understand how this works, but
'in' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
(Other definitions for interior that I've seen before include "Inland region" , "Situated within" , "Land away from the coast" , "Heartland" , "The inside of anything" .)