his·ti·dine (hĭs'tĭ-dēn', -dĭn)
n.
An essential amino acid, C₆H₉N₃O₂, important for the growth and repair of tissues.

[HIST(O)- + -ID(E) + -INE².]

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The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.

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