antivitamin

noun

an·ti·vi·ta·min ˈan-ti-ˌvī-tə-mən

ˈan-tī-

British usually -ˌvi-

: a substance that makes a vitamin metabolically ineffective

Word History

First Known Use

1927, in the meaning defined above

Time Traveler

The first known use of antivitamin was in 1927

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Browse Nearby Words

antivirus

antivitamin

anti-vivisection

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Cite this Entry

Style

“Antivitamin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/antivitamin. Accessed 31 Oct. 2025.

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Medical Definition

antivitamin

noun

an·ti·vi·ta·min

ˈant-i-ˌvīt-ə-mən, ˈan-ˌtī-, British usually -ˌvit-

: a substance that makes a vitamin metabolically ineffective

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