Swallow hurriedly (4)
I believe the answer is:
gulp
'swallow hurriedly' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for gulp that I've seen before include "Swallow audibly" , "Swallow hurriedly" , "Noise made when swallowing too quickly" , "Swallow noisily" , "Swallow quickly" .)