Deposit on teeth (6)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">deposit on teeth</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for tartar that I've seen before include "Deposit that forms on teeth" , "Incrustation on teeth and gums" , "ancient Mongolian" , "A sauce to go with fish" , "For instance, Genghis Khan" .)
(Other definitions for plaque that I've seen before include "Substance that forms on teeth encouraging bacteria" , "dental hygiene problem" , "Film on teeth that encourages caries" , "Memorial slab" , "Dental coating" .)