Pip-squeak (6)
I believe the answer is:
squirt
'pip-squeak' is the definition.
(I know that pip-squeak can be written as squirt)
This is all the clue.
(Other definitions for squirt that I've seen before include "Spirt" , "Spurt, jet" , "Eject in a jet" , "Thin jet of liquid" , "Short emission" .)