Show a third of retailers in the money (8)
I believe the answer is:
pretence
'show' is the definition.
(a pretence can mean something done for show)
'a third of retailers in the money' is the wordplay.
'a third of retailers' becomes 'ret' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'in the' indicates putting letters inside.
'money' becomes 'pence' (I've seen this before).
'ret' put into 'pence' is 'PRETENCE'.
Can you help me to learn more?
(Other definitions for pretence that I've seen before include "it can't be true!" , "Make-believe, or false claim to merit" , "Affectation" , "Ten creep (anag.)" , "Act of make-believe" .)