Roast meat sat uneasily (7)
I believe the answer is:
lambast
'roast' is the definition.
(I've seen this before)
'meat sat uneasily' is the wordplay.
'meat' becomes 'lamb' (lamb is a kind of meat).
'uneasily' indicates an anagram.
'sat' is an anagram of 'ast'.
'lamb'+'ast'='LAMBAST'
(Other definitions for lambast that I've seen before include "Thrash" , "Beat severely" , "Harshly criticise" , "Roast" , "Bash" .)