Lubricant

Substance introduced to reduce friction between surfaces in mutual contact

A lubricant (sometimes shortened to lube) is a substance that helps to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated when the surfaces move. It may also have the function of transmitting forces, transporting foreign particles, or heating or cooling the surfaces. A lubricant's effectiveness against friction is measured as its lubricity and the study of lubrication in material science is known as tribology.

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