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definitions

macronutrient

[mak-roh-noo-tree-uh nt, -nyoo-]
noun
  1. Nutrition. any of the nutritional components of the diet that are required in relatively large amounts: protein, carbohydrate, fat, and the macrominerals.
  2. Botany. any of the three chemical elements required by plants in relatively large amounts: nitrogen, phosphorus, and potassium.
Compare micronutrient.

Origin of macronutrient

First recorded in 1940–45; macro- + nutrient
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for macronutrient

macronutrient

noun
  1. any substance, such as carbon, hydrogen, or oxygen, that is required in large amounts for healthy growth and development
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
macronutrient in Medicine

macronutrient

[măk′rō-nōō′trē-ənt]
n.
  1. A nutrient required in large amounts for the normal growth and development of an organism.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.