Favourite dog, say (3)
I believe the answer is:
pet
I believe this is a double definition.
'favourite' is the first definition.
(synonyms)
'dog say' is the second definition.
(dog is an example)
(Other definitions for pet that I've seen before include "Preferred" , "Cherished favourite" , "Loved domestic animal" , "Darling; fit of sulks" , "Favourite, perhaps a domestic animal" .)