Spirit seen in strange light (5)
I believe the answer is:
angel
'spirit' is the definition.
'in strange light' is the wordplay.
'in' indicates a hidden word.
'ANGEL' can be found hidden inside 'strange light'.
'seen' is the link.
(Other definitions for angel that I've seen before include "Heavenely messenger" , "Glean (anag.)" , "Investor in a theatrical venture" , "One usually obliging" , "Heavenly messenger" .)