Afraid and stupid, it came back (5)
I believe the answer is:
timid
'afraid' is the definition.
('timid' is associated in meaning with 'afraid')
'stupid it came back' is the wordplay.
'stupid' becomes 'dim' (I've seen this before).
'came back' says the letters should be written in reverse.
'dim'+'it'='dimit'
'dimit' backwards is 'TIMID'.
'and' acts as a link.
(Other definitions for timid that I've seen before include "afraid to speak out?" , "Inclined to avoid people" , "Gutless" , "Pusillanimous" , "Easily scared" .)