methylxanthine

noun

meth·​yl·​xan·​thine ˌme-thəl-ˈzan-ˌthēn How to pronounce methylxanthine (audio)
: a methylated xanthine derivative (such as caffeine, theobromine, or theophylline)

Examples of methylxanthine in a Sentence

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Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Most of us are familiar with the most talked about methylxanthine — caffeine. — Adele Jackson-Gibson, Good Housekeeping, 1 Nov. 2022 The shells contain two chemical compounds called methylxanthines that are also found in chocolate — theobromine and caffeine. — Tim Johnson, Chicago Tribune, 14 May 2023

Word History

First Known Use

1949, in the meaning defined above

Time Traveler
The first known use of methylxanthine was in 1949

Rhymes for methylxanthine

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Browse Nearby Words

methyl rubber
methylxanthine
methyl yellow
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Cite this Entry

“Methylxanthine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/methylxanthine. Accessed 7 Jul. 2026.

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Medical Definition

methylxanthine

noun
meth·​yl·​xan·​thine ˌmeth-əl-ˈzan-ˌthēn How to pronounce methylxanthine (audio)
: a methylated xanthine derivative (as caffeine, theobromine, or theophylline)

More from Merriam-Webster on methylxanthine

Britannica.com: Encyclopedia article about methylxanthine

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