By the previous wife, do right (5)
I believe the answer is:
exact
'right' is the definition.
(similar in meaning)
'by the previous wife do' is the wordplay.
'by' means one lot of letters go next to another.
'the previous' becomes 'ex' (prefix meaning former or onetime).
'wife do' becomes 'act' (I am not sure about this - if you are sure you should believe this answer much more).
'ex'+'act' is 'EXACT'.
Can you help me to learn more?
(Other definitions for exact that I've seen before include "without rounding" , "Demand, extort" , "Precise, accurate" , "As a right, demand" , "Precise - demand" .)