Cover for organ of English king in a panic (7)
I believe the answer is:
earflap
'cover for organ' is the definition.
(cover for an ear)
'english king in a panic' is the wordplay.
'english' becomes 'E' (abbreviation).
'king' becomes 'R' (abbreviation of Latin rex).
'in' is an insertion indicator.
'panic' becomes 'flap' (getting in a flap is panicking).
'a'+'flap'='aflap'
'r' going into 'aflap' is 'arflap'.
'e'+'arflap'='EARFLAP'
'of' acts as a link.
(Other definitions for earflap that I've seen before include "ski gear?" , "Part of headgear" , "Winter hat feature" .)