Take hold (5)
'take hold' is the definition.
(I've seen this in another clue)
This is all the clue.
(Another definition for set in that I've seen is " Become established".)
'take hold' is the definition.
(grasping is a kind of taking hold)
This is the entire clue.
(Other definitions for grasp that I've seen before include "Hold - understanding" , "Hold tightly" , "Clutch" , "Lay hold of" , "Seize, hold firmly" .)