Cat required - there are quite a few in the pound (5)
I believe the answer is:
ounce
I believe this is a double definition.
'cat' is the first definition.
(ounce can mean a snow leopard)
'there are quite a few in the pound' is the second definition.
(I've seen this before)
'required' is the link.
(Other definitions for ounce that I've seen before include "one of sixteen in a pound" , "Unit of weight - snow leopard" , "Unit equal to about 28 grams" , "Light weight coming in on cue" , "Large cat" .)