Star's gear held without case (5)
I believe the answer is:
rigel
'star's' is the definition.
(star in the constellation Orion)
'gear held without case' is the wordplay.
'gear' becomes 'rig' (rig is a kind of gear).
'without case' says to take the centre (letters which encase the word are removed).
The central letters of 'held' are 'el'.
'rig'+'el'='RIGEL'
(Other definitions for rigel that I've seen before include "Brightest star in Orion" , "shiner" , "Orion's brightest star" .)