Popular pets
I believe the answer is:
cats
'popular pets' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for cats that I've seen before include "Musical; jazz fans" , "1981 Lloyd Webber musical" , "Musical (felines?)" , "Spectacular Llyod Webber feline musical" , "Famous feline Lloyd Webber musical" .)