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essential amino acid

noun Biochemistry.

any amino acid that is required by an animal for growth but that cannot be synthesized by the animal's cells and must be supplied in the diet.

Origin of essential amino acid

First recorded in 1935–40
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
essential amino acid in Medicine

essential amino acid

n.

An alpha-amino acid that is required for protein synthesis but cannot be synthesized by humans and must be obtained in the diet.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.