Lottery pay-out wife wasted — that’s a knock (7)
I believe the answer is:
innings
'that's a knock' is the definition.
(I've seen this before)
'lottery pay-out wife wasted' is the wordplay.
'lottery pay-out' becomes 'winnings' (money won in the lottery).
'wife' becomes 'w' (abbreviation).
'wasted' indicates named letters should be taken away.
'winnings' with 'w' removed is 'INNINGS'.
(Other definitions for innings that I've seen before include "Time at the crease for one batsman (or eleven)" , "Turns for the batsman" , "part of cricket match" , "Batsman's turn at the crease" , "Period at the wicket" .)