Answer, understood, read out again (4)
I believe the answer is:
anew
'again' is the definition.
(synonyms)
'answer understood read out' is the wordplay.
'answer' becomes 'a' (abbreviation eg in Q and A).
'understood' becomes 'knew' (know can mean to understand or appreciate).
'read out' shows a homophone (sound like).
'knew' sounds like 'new'.
'a'+'new'='ANEW'
(Other definitions for anew that I've seen before include "Once more (poetic)" , "Again but differently" , "Wane in a different way, again" , "Afresh" , "From the beginning again" .)