Definition of tartar

• n. - A reddish crust or sediment in wine casks, consisting essentially of crude cream of tartar, and used in marking pure cream of tartar, tartaric acid, potassium carbonate, black flux, etc., and, in dyeing, as a mordant for woolen goods; -- called also argol, wine stone, etc.
• n. - A correction which often incrusts the teeth, consisting of salivary mucus, animal matter, and phosphate of lime.
• n. - 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.
• n. - A person of a keen, irritable temper.
• a. - Of or pertaining to Tartary in Asia, or the Tartars.
• n. - See Tartarus.