What does "tartar" mean?

Tartar: A correction which often incrusts the teeth, consisting of salivary mucus, animal matter, and phosphate of lime. Cream of tartar. (Chem.) See under Cream. -- Tartar emetic (Med. Chem.), a double tartrate of potassium and basic antimony. It is a poisonous white crystalline substance having a sweetish metallic taste, and used in medicine as a sudorific and emetic.

Additional senses

  1. 2.Etym: [Per. Tatar, of Tartar origin.] A native or inhabitant of Tartary in Asia; a member of any one of numerous tribes, chiefly Moslem, of Turkish origin, inhabiting the Russian Europe; -- written also, more correctly but less usually, Tatar.
  2. 3.A person of a keen, irritable temper. To catch a tartar, to lay hold of, or encounter, a person who proves too strong for the assailant. [Colloq.]
  3. 4.Of or pertaining to Tartary in Asia, or the Tartars.
  4. 5.See Tartarus. Shak.

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