Grow pale when accepting it (6)
I believe the answer is:
whiten
'grow pale' is the definition.
(thesaurus)
'when accepting it' is the wordplay.
'accepting' is an insertion indicator (inserted letters are accepted).
'when' going around 'it' is 'WHITEN'.
(Other definitions for whiten that I've seen before include "Become less colourful" , "Blanch" , "New hit (anag.)" , "Bleach" , "Turn pale" .)