Latch (4)
I believe the answer is:
bolt
'latch' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for bolt that I've seen before include "Type of lightning" , "Lock - run away - gobble - lightning flash - cloth roll" , "Flee with door-locking device" , "Find a bar" , "Run away; fasten (door)" .)