Rejection of apartment? (4,7)

'rejection of apartment?' is the definition.
The definition suggests a singular noun which matches the answer.

'rejection of apartment?' is the wordplay.
I cannot really see how this works, but
'rejection' could be 'refusal' (I've seen this in another clue) and 'refusal' is located in the answer.
'apartment?' could be 'flat' ('flat' can be a synonym of 'apartment') and 'flat' is found in the answer.
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?