Crossword Genius

Vehicle with black on - soot? (6)

Ross

I believe the answer is:

carbon

'soot?' is the definition.
(soot is a kind of carbon)

'vehicle with black on' is the wordplay.
'vehicle' becomes 'car' (car is a kind of vehicle).
'with' means one lot of letters go next to another.
'black' becomes 'b' (as in pencil classifications).
'car'+'b'+'on'='CARBON'

(Other definitions for carbon that I've seen before include "Substance" , "Element of glass" , "Elementary" , "Non-metallic element, C" , "US five-cent coin" .)

I've seen this clue in The Telegraph.
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