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definitions

megavitamin

[meg-uh-vahy-tuh-min; British also meg-uh-vit-uh-min]

adjective

of, relating to, or using very large amounts of vitamins: megavitamin therapy.Compare orthomolecular.

noun

megavitamins, doses of vitamins much larger than the recommended dietary allowances.

Origin of megavitamin

First recorded in 1965–70; mega- + vitamin
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
megavitamin in Medicine

megavitamin

[mĕg′ə-vī′tə-mĭn]

n.

A dose of a vitamin greatly exceeding the amount required to maintain health.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.