Old fool embracing English cat (6)
I believe the answer is:
ocelot
'cat' is the definition.
(type of wild cat)
'old fool embracing english' is the wordplay.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'fool' becomes 'clot' (I've seen this in other clues).
'embracing' is an insertion indicator.
'english' becomes 'E' (abbreviation).
'clot' enclosing 'e' is 'celot'.
'o'+'celot'='OCELOT'
(Other definitions for ocelot that I've seen before include "Type of American wildcat" , "Wild cat, native to Central and South America - loo etc (anag)" , "Nocturnal wild cat of Central and South America" , "Feline of South and Central America" , "Big cat" .)