Tartar

n. [Fr. tartre, Pr. tartari, Sp., Pg., & It. tartaro, L. Lat. tartarum, L. Gr. τά ρταρον.]

1. (Chem.) An acid concrete salt, deposited from wines completely fermented, and adhering to the sides of the casks in the form of a hard crust. It is white or red, the white being the more highly esteemed. When pure, it is called cream of tartar, and when crude, argal, or argol. In the latter state, it is much used as a flux in the assaying of ores.
2. A concretion which often incrusts the teeth, consisting of salivary mucus, animal matter, and phosphate of lime.
3. A person of a keen, irritable temper.
4. (Geog.) A native or inhabitant of Tartary; — written also, more correctly, but less usually, Tutar.

Tartar-emetic (Chem.), a double salt, consisting of tartaric acid in combination with potassa and protoxide of antimony. Brande.—To catch a Tartar, to lay hold of or encounter a person who proves too strong for the assailant.