Stay on the wing (6)
I believe the answer is:
reside
'stay' is the definition.
(I've seen this in other clues)
'on the wing' is the wordplay.
'on' becomes 're' ('on' can be mean 'with reference to').
'the wing' becomes 'side' (eg the wings of a building are on its sides).
're'+'side'='RESIDE'
(Other definitions for reside that I've seen before include "Dwell - settle" , "Make one's home permanently" , "Lodge" , "Live (at an address)" , "Dwell, be present (in)" .)