Retch (5)
I believe the answer is:
heave
'retch' is the definition.
(I know that retch can be written as heave)
This is all the clue.
(Other definitions for heave that I've seen before include "Haul - retch" , "Lift or throw with great effort" , "Retch - lift using much effort" , "Pull hard; (sea) swell" , "Pull - retch" .)