Manx or Persian (3)
I believe the answer is:
cat
I believe this clue is a double definition.
'manx' is the first definition.
(I've seen this in another clue)
'persian' is the second definition.
(Persian is a type of cat)
(Other definitions for cat that I've seen before include "one's pyjamas? They're an excellent thing" , "See 21" , "Tiger, for instance" , "Eg, tiger, lion" , "Tabby" .)