Still in charge after endless fluster (6)
I believe the answer is:
static
'still' is the definition.
('static' can be a synonym of 'still')
'in charge after endless fluster' is the wordplay.
'in charge' becomes 'ic'.
'after' says to put letters next to each other.
'endless' means to remove the last letter.
'fluster' becomes 'state' (both can mean a state of panic).
'state' with its final letter removed is 'stat'.
'ic' put after 'stat' is 'STATIC'.
(Other definitions for static that I've seen before include "Unmoving like kind of electricity" , "That's shocking!" , "Inactive, motionless" , "Motionless like some kind of electricity" , "Changeless" .)