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

Example Sentences

Recent Examples on the Web Most of us are familiar with the most talked about methylxanthine — caffeine. Adele Jackson-gibson, Good Housekeeping, 1 Nov. 2022

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'methylxanthine.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

1949, in the meaning defined above

Time Traveler
The first known use of methylxanthine was in 1949

Dictionary Entries Near methylxanthine

Cite this Entry

“Methylxanthine.” Dictionary, Merriam-Webster, Accessed 1 Dec. 2022.

Medical Definition



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

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