Roman statesman gives Tom nothing (4)
I believe the answer is:
cato
'roman statesman' is the definition.
(I've seen this before)
'tom nothing' is the wordplay.
'tom' becomes 'cat' (I have seen 'A tom ' mean 'cat' so perhaps 'tom' could also mean 'cat').
'nothing' becomes 'o' (looks like zero - 0).
'cat'+'o'='CATO'
'gives' is the link.
(Other definitions for cato that I've seen before include "Roman statesman" , "Senator" , "Ancient Roman censor" , "Marcus Porcius - , Roman politician, censor" , "classical writer" .)