Separate answer? Dad right! (5)
I believe the answer is:
apart
'separate' is the definition.
('apart' can be similar in meaning to 'separate')
'answer? dad right' is the wordplay.
'answer?' becomes 'a' (abbreviation eg in Q and A).
'dad' becomes 'pa' ('pa' can be a synonym of 'dad').
'right' becomes 'rt'.
'a'+'pa'+'rt'='APART'
(Other definitions for apart that I've seen before include "Divided" , "In private" , "cut off from others" , "Separated or at a distance" , "Asunder" .)