During flights, we push back seats (4)
I believe the answer is:
pews
'seats' is the definition.
(pew is a kind of seat)
'during flights we push back' is the wordplay.
'during' indicates a hidden word.
'back' says the letters should be written backwards.
'swep' is hidden within 'flights we push'.
'swep' back-to-front is 'PEWS'.
(Other definitions for pews that I've seen before include "Church seats" , "Church seating" , "Church benches" .)