Crossword Genius

Type of sugar not popular for tooth (4)

Ross

I believe the answer is:

cane

'type of sugar' is the definition.
(cane sugar)

I can't explain the remainder of the clue.

(Other definitions for cane that I've seen before include "Flog" , "Rod for beating" , "Stem of palm" , "Kind of sugar?" , "Beat; sugar producer" .)

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