Turkey a cat beat decisively (7)
I believe the answer is:
trounce
'beat decisively' is the definition.
(I've seen this in another clue)
'turkey a cat' is the wordplay.
'turkey' becomes 'tr' (abbreviation eg in internet addresses).
'a cat' becomes 'ounce' (ounce can mean a snow leopard).
'tr'+'ounce'='TROUNCE'
(Other definitions for trounce that I've seen before include "Counter (anag) - defeat" , "National flower of South Africa" , "Beat heavily" , "Utterly defeat" , "Rout" .)