Bad loser in lawsuit is a dish (9)
I believe the answer is:
casserole
'dish' is the definition.
(I've seen this before)
'bad loser in lawsuit' is the wordplay.
'bad' is an anagram indicator.
'in' indicates putting letters inside.
'lawsuit' becomes 'case' ('case' can be a synonym of 'lawsuit').
'loser' is an anagram of 'serol'.
'serol' placed within 'case' is 'CASSEROLE'.
'is a' acts as a link.
(Other definitions for casserole that I've seen before include "Oven dish" , "Stew-dish" , "Large cooking dish" , "Slow-cooked dish" , "Meat dish" .)