More than one current royal castle dismissing soldiers (5)
I believe the answer is:
winds
'more than one current' is the definition.
(I have seen 'Currents of air ' mean 'winds' so perhaps 'currents' could also mean 'winds')
'royal castle dismissing soldiers' is the wordplay.
'royal castle' becomes 'windsor' (I've seen this before).
'dismissing' is a deletion indicator.
'soldiers' becomes 'OR' (military abbreviation for other ranks).
'windsor' with 'or' taken away is 'WINDS'.
(Other definitions for winds that I've seen before include "Currents of air" , "Coils" .)