Associate dropping head, glower? (5)
I believe the answer is:
ember
'glower?' is the definition.
(something which glows)
'associate dropping head' is the wordplay.
'associate' becomes 'member' (member is a kind of associate).
'dropping head' means to remove the first letter.
'member' with its initial letter removed is 'EMBER'.
(Other definitions for ember that I've seen before include "Glowing, smouldering piece of coal or wood" , "Still smouldering fragment of wood or coal" , "Wood still burning" , "Glowing coal; prayer (Days)" , "Glowing remainder of a fire" .)