Seemingly, boy listens for a change (10)
I believe the answer is:
ostensibly
'seemingly' is the definition.
(I know that seemingly can be written as ostensibly)
'boy listens for a change' is the wordplay.
'for a change' is an anagram indicator.
'boy'+'listens'='boylistens'
'boylistens' with letters rearranged gives 'OSTENSIBLY'.
(Other definitions for ostensibly that I've seen before include "on the face of it" , "to all intents and purposes" , "Evidently" , "Seemingly" .)