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stearic acid ste·ar·ic acid (stē-ār'ĭk, stēr'ĭk)
A colorless, odorless, waxlike fatty acid occurring naturally in animal and vegetable fats and used in pharmaceutical preparations, ointments, soaps, and suppositories.
one of the most common long-chain fatty acids, found in combined form in natural animal and vegetable fats. Commercial "stearic acid" is a mixture of approximately equal amounts of stearic and palmitic acids and small amounts of oleic acid. It is employed in the manufacture of candles, cosmetics, shaving soaps, lubricants, and pharmaceuticals.