A burning issue that's illuminating (4)
I believe the answer is:
wick
'a burning issue' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Maybe there's an association between them I don't understand?
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for wick that I've seen before include "fishing port" , "Candle cord - Scottish town" , "Beginners" , "Candle fibre" , "Highland burgh" .)