It may be bid (5)
I believe the answer is:
adieu
'it may be bid' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for adieu that I've seen before include "Adios, Arrivederci" , "Leave" , "See you later" , "12 Down" , "Goodbye, mademoiselle" .)