tar ‧ tar /ˈtɑːtə $ ˈtɑːrtər/ BrE AmE noun
[ Date: 1300-1400 ; Language: Medieval Latin ; Origin: tartarum ]
1 . [uncountable] a hard substance that forms on your teeth
2 . [countable] informal British English someone who has a violent temper:
She’s a real tartar.