Muscle twitch (3)
'muscle twitch' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for spasm that I've seen before include "cramp" , "Pretend to have (injury)" , "Muscle twitch" , "Involuntary contraction of muscles" , "Sudden involuntary contraction of a muscle" .)
'muscle twitch' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for tic that I've seen before include "Facial muscle spasm" , "Localised habitual twitch, especially to the face" , "Fuel oil" , "jerk" , "Convulsion" .)