laughing (9)
There are a few possibilities for this:
chortling
'laughing' is the definition.
(riant can mean cheerful or laughing)
This is the entire clue.
(Other definitions for riant that I've seen before include "Laughing" , "merry" , "patently amused" .)
(Other definitions for hyena that I've seen before include "Carrion-feeding carnivore" , "Carnivore with sloping body" , "African carrion-feeder" , "One laughs loud" , "Dog-like nocturnal mammal of Africa and southern Asia" .)
'laughing' is the definition.
(chortling is a kind of laughing)
This is the entire clue.
(Another definition for chortling that I've seen is " Chuckling".)