trimethoprim

noun

tri·meth·o·prim trī-ˈme-thə-ˌprim

: a synthetic antibacterial and antimalarial drug C₁₄H₁₈N₄O₃ used alone or in combination with sulfamethoxazole

Examples of trimethoprim in a Sentence

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He was prescribed Bactrim, a sulfamethoxazole-trimethoprim antibiotic commonly used to treat Cyclosporiasis, and said his symptoms improved within several hours of taking the first pill. — Janelle Mella, Charlotte Observer, 21 July 2026 Cyclospora can be treated with the combination antibiotic trimethoprim-sulfamethoxazole, also known as Bactrim, Septra or Cotrim. — Cindy Krischer Goodman, Sun Sentinel, 17 July 2026 Sulfamethoxazole and trimethoprim are types of antibiotics used to treat bacterial infections, according to the Cleveland Clinic. — Chad Murphy, USA Today, 14 July 2026 Treatment is seven to 10 days of the combination antibiotic sulfamethoxazole-trimethoprim, which is sold as Bactrim or Septra. — Brenda Goodman, CNN Money, 13 July 2026 See All Example Sentences for trimethoprim

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

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trimethine

trimethoprim

trimethoxy-

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Style

“Trimethoprim.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/trimethoprim. Accessed 2 Aug. 2026.

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Medical Definition

trimethoprim

noun

tri·meth·o·prim trī-ˈmeth-ə-ˌprim

: 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

trimethoprim

noun

Examples of trimethoprim in a Sentence

Word History

Browse Nearby Words

Cite this Entry

Medical Definition

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