Mad liar shot officer (7)
I believe the answer is:
admiral
'officer' is the definition.
(admiral is a kind of officer)
'mad liar shot' is the wordplay.
'shot' indicates anagramming the letters.
'mad'+'liar'='madliar'
'madliar' anagrammed gives 'ADMIRAL'.
(Other definitions for admiral that I've seen before include "Navy chief" , "Red butterfly in charge of the fleet" , "Senior naval officer" , "Blake, for one" , "Naval officer of high rank" .)