Take off, as a cap (7)
I believe the answer is:
unscrew
(Other definitions for unscrew that I've seen before include "Take off (eg, a lid)" , "Take the top off" , "Twist and open" , "Loosen" , "Unfasten by twisting" .)
I believe the answer is:
unscrew
(Other definitions for unscrew that I've seen before include "Take off (eg, a lid)" , "Take the top off" , "Twist and open" , "Loosen" , "Unfasten by twisting" .)