Tablet that's stuck on teeth (6)

I believe the answer is:

plaque

I believe this clue is a double definition.

'tablet' is the first definition.
(thesaurus)

'that's stuck on teeth' is the second definition.

(Other definitions for plaque that I've seen before include "Memorial plate" , "Unhygienic stuff that grows on teeth" , "Memorial slab" , "Film on tooth" , "Sticky deposit on teeth" .)

I've seen this clue in The Times.

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