Pigeon quietly flying off further from centre (5)
I believe the answer is:
outer
'further from centre' is the definition.
(I've seen this before)
'pigeon quietly flying off' is the wordplay.
'pigeon' becomes 'pouter' (pouter is a type of pigeon).
'quietly' becomes 'p' (p for piano and quiet).
'flying off' suggests deleting specific letters.
'pouter' with 'p' taken out is 'OUTER'.
(Other definitions for outer that I've seen before include "Exterior or external, like space" , "Poor shot" , "Route (anag.)" , "This space is beyond earth's atmosphere" , "External; part of archery target" .)