Cheep (5)
I believe the answer is:
chirp
'cheep' is the definition.
(I know that cheep can be written as chirp)
This is the entire clue.
(Other definitions for chirp that I've seen before include "Make sound like grasshopper" , "Grasshopper's noise" , "Twitter" , "Fledgling's sound" , "Short sharp tone of grasshopper" .)