It could take flight if bait's regularly taken (4)
I believe the answer is:
ibis
'it could take flight' is the definition.
(ibis is a type of bird)
'if bait's regularly taken' is the wordplay.
'regularly taken' indicates alternate letters (letters taken at regular intervals).
'if'+'baits'='ifbaits'
The alternate letters of 'ifbaits' are 'IBIS'.
(Other definitions for ibis that I've seen before include "Large wading birds with down-curved bills" , "seaside feeder?" , "Revered bird" , "Bird, sacred to ancient Egyptians" , "Winger" .)