Tighten as fist (6)

I believe the answer is:
clench
(Other definitions for clench that I've seen before include "Settle; embrace" , "Grip tightly" , "Hold tightly and firmly" , "Get a grip on" , "Grasp firmly" .)
I believe the answer is:
clench
(Other definitions for clench that I've seen before include "Settle; embrace" , "Grip tightly" , "Hold tightly and firmly" , "Get a grip on" , "Grasp firmly" .)