May she look after girl in empty nursery? (5)
I believe the answer is:
nanny
'may she look after' is the definition.
(a nanny looks after children)
'girl in empty nursery?' is the wordplay.
'girl' becomes 'ann' (woman's name).
'in' means one lot of letters goes inside another.
'empty' means to remove the middle letters.
'nursery' with its centre removed is 'ny'.
'ann' placed inside 'ny' is 'NANNY'.
(Other definitions for nanny that I've seen before include "Producer of milk" , "Overprotective government deplored by Thatcher" , "Child's nurse or female goat" , "Issue tender" , "Home help" .)