Game, chirpy little thing (7)
I believe the answer is:
cricket
This clue is a double definition.
'game' is the first definition.
(I know that cricket is a type of outdoor game)
'chirpy little thing' is the second definition.
(the insect)
(Other definitions for cricket that I've seen before include "Summer sport" , "Insect - sport" , "English game or chirping insect" , "Insect with long leg" , "Game - "basically baseball on Valium" (Robin Williams)" .)