Track round leading lady's houses? (7)
I believe the answer is:
terrace
'houses?' is the definition.
(I've seen this before)
'track round leading lady's' is the wordplay.
'track' becomes 'trace' (tracing is a kind of tracking).
'round' means one lot of letters goes inside another.
'leading lady' becomes 'ER' (Elizabeth Regina).
'trace' going around 'er' is 'TERRACE'.
(Other definitions for terrace that I've seen before include "steps in stadium" , "Stadium's standing area" , "Stadium spectators' area" , "Row of housing" , "flat roof" .)