Frolic, romp (7)
I believe the answer is:
skylark
I believe this is a double definition.
'frolic' is the first definition.
(I know that frolic can be written as skylark)
'romp' is the second definition.
(I know that romp can be written as skylark)
(Other definitions for skylark that I've seen before include "subject of 11 [ODE]" , "very high singer" , "Passerine bird" , "Bird that sings aloft" , "flier" .)