trimethoprim

noun

tri·​meth·​o·​prim trī-ˈme-thə-ˌprim How to pronounce trimethoprim (audio)
: a synthetic antibacterial and antimalarial drug C14H18N4O3 used alone or in combination with sulfamethoxazole

Examples of trimethoprim 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.
Next came Macrobid, a combination treatment of trimethoprim and sulfamethoxazole. — Natalie Ma, STAT, 31 Oct. 2021 Antibiotics are used to treat donovanosis, including azithromycin, doxycycline, ciprofloxacin, erythromycin and trimethoprim-sulfamethoxazole. — Scott Gleeson, USA TODAY, 26 Oct. 2021

Word History

Etymology

tri- + meth- + -prim (by shortening & alteration from pyrimidine)

First Known Use

1964, in the meaning defined above

Time Traveler
The first known use of trimethoprim was in 1964

Rhymes for trimethoprim

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Browse Nearby Words

trimethine
trimethoprim
trimethoxy-
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Cite this Entry

“Trimethoprim.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/trimethoprim. Accessed 3 Apr. 2025.

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Medical Definition

trimethoprim

noun
tri·​meth·​o·​prim trī-ˈmeth-ə-ˌprim How to pronounce trimethoprim (audio)
: a synthetic antibacterial drug C14H18N4O3 used alone especially to treat urinary tract infections and Pneumocystis carinii pneumonia and in combination with sulfamethoxazole to treat these as well as other infections (as shigellosis or acute otitis media) see bactrim

More from Merriam-Webster on trimethoprim

Britannica.com: Encyclopedia article about trimethoprim

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