Scottish candle centre (4)
I believe the answer is:
wick
This clue might be a double definition.
'scottish candle' is the first definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Maybe you can see an association between them that I don't see?
'centre' is the second definition.
(I have seen 'Centre of candle ' mean 'wick' so perhaps 'centre' could also mean 'wick')
Can you help me to learn more?
(Other definitions for wick that I've seen before include "Cord conveying liquid by capillary action" , "Northern town" , "Candle's thread" , "Candle fibre" , "See 1" .)