Jump suit's ultimate fascinator? (6)
I believe the answer is:
twitch
'jump' is the definition.
(I've seen this before)
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for twitch that I've seen before include "Spasmodic muscle contraction" , "Muscle spasm" , "Sudden jerky movement; pang" , "Quiver or contract spasmodically, as eye may" , "Sudden muscular spasm" .)