Definition of "tartar" []

• Dentistry A hard yellowish deposit on the teeth, consisting of organic secretions and food particles deposited in various salts, such as calcium carbonate. Also called calculus. (noun)
• A reddish acid compound, chiefly potassium bitartrate, found in the juice of grapes and deposited on the sides of casks during winemaking. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "He recognized, however, that cleansing of the teeth properly often became impossible by any scrubbing method, no matter what the dentifrice used, because of the presence of what we call tartar and what he called hardened limosity or limyness (_limosité endurcie_)."
• "I leavened the dough with baking soda and cream of tartar in place of baking powder (although cream of tartar is often the main component in baking powder) because that is the traditional leavening combination for snickerdoodles."
• "Their french fries are ok, but sometimes a girl just needs some fried potato with her seafood … so I doctor them up with a dip in tartar sauce and a sprinkle of Old Bay seasoning."