Tooth deposit (6)
I believe the answer is:
tartar
'tooth deposit' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for tartar that I've seen before include "Fearsome person: kind of sauce" , "Unmanageable sort" , "A ferocious person" , "This sauce often goes with fish" , "For instance, Genghis Khan" .)