Incandescent tirade about withdrawal of benefit (7)
I believe the answer is:
radiant
'incandescent' is the definition.
(I've seen this before)
'tirade about withdrawal of benefit' is the wordplay.
'tirade' becomes 'rant' (both can mean an angry outburst).
'about' means one lot of letters goes inside another.
'withdrawal of' says the letters should be written backwards.
'benefit' becomes 'aid' (I've seen this in another clue).
'aid' reversed gives 'dia'.
'rant' placed around 'dia' is 'RADIANT'.
(Other definitions for radiant that I've seen before include "Luminous" , "Incandescent" , "Splendid; heater type" , "Lit up" , "Sending out light, glowing" .)