Pay, say, about half a dollar (6)
I believe the answer is:
salary
'pay' is the definition.
(synonyms)
'say about half a dollar' is the wordplay.
'about' is an insertion indicator.
'half a' indicates taking half.
'dollar' cut in half is 'lar'.
'say' enclosing 'lar' is 'SALARY'.
(Other definitions for salary that I've seen before include "Regular monthly wage" , "(Employee's) pay" , "Regular income from employment" , "payment only for non-manual workers" , "Regular earnings" .)