Expectorate (4)
I believe the answer is:
spit
'expectorate' is the definition.
(I know that spit is a kind of expectorate)
This is all the clue.
(Other definitions for spit that I've seen before include "nearly a foot deep" , "Slaver" , "Rain in scattered drops" , "Eject with violence" , "Coastal feature, tongue of sand" .)