Emperor snatching victory: US uneasy (7)
I believe the answer is:
nervous
'uneasy' is the definition.
(I know that uneasy can be written as nervous)
'emperor snatching victory us' is the wordplay.
'emperor' becomes 'nero' (Roman emperor).
'snatching' indicates putting letters inside.
'victory' becomes 'v'.
'nero' enclosing 'v' is 'nervo'.
'nervo'+'us'='NERVOUS'
(Other definitions for nervous that I've seen before include "Edgy" , "Anxious, uneasy" , "'Apprehensive, uneasy (7)'" , "in a stew" , "stewing" .)