Hat deprived fellow dropped (5)
I believe the answer is:
beret
'hat' is the definition.
(thesaurus)
'deprived fellow dropped' is the wordplay.
'deprived' becomes 'bereft' (I've seen this before).
'fellow' becomes 'f' (abbreviation - of a society etc.).
'dropped' is a deletion indicator.
'bereft' with 'f' taken out is 'BERET'.
(Other definitions for beret that I've seen before include "Cap with no brim" , "cap in France?" , "French style cap" , "Soft round cap without a peak" , "Part of kit" .)