tamoxifen

noun

ta·mox·i·fen tə-ˈmäk-sə-ˌfen

: an estrogen antagonist C₂₆H₂₉NO used in the form of its citrate especially to treat postmenopausal breast cancer

Examples of tamoxifen in a Sentence

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Peet, who had been screened since her late 30s because of dense breast tissue and prior benign lumps, was treated with a lumpectomy and radiation and is now on tamoxifen. — Samantha Agate, Kansas City Star, 14 Oct. 2026 Peet underwent a lumpectomy and radiation and now takes tamoxifen, a drug that blocks cancer cells from using estrogen and progesterone to grow. — Samantha Agate, Miami Herald, 14 Oct. 2026 After a moment’s thought, Greenwald told her to do the lumpectomy—and the tamoxifen, which would cut the chance of cancer recurrence in half. — Melanie Thernstrom, New Yorker, 29 June 2026 If the findings are confirmed, the risk score could help doctors tailor recommendations for surveillance intensity and risk-reduction strategies, including medications like tamoxifen or aromatase inhibitors, specifically for those high-risk women, says Roy. — Emily Kay Votruba, EverydayHealth.com, 2 Oct. 2025 See All Example Sentences for tamoxifen

Word History

Etymology

probably by recombination & alteration of trans-, oxy, and clomiphene

First Known Use

1972, in the meaning defined above

Time Traveler

The first known use of tamoxifen was in 1972

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Tamonea

tamoxifen

tamp

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Style

“Tamoxifen.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tamoxifen. Accessed 20 Oct. 2026.

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Medical Definition

tamoxifen

noun

ta·mox·i·fen ta-ˈmäk-si-ˌfen

: a selective estrogen receptor modulator that acts as an estrogen antagonist in breast tissue and is administered orally in the form of its citrate C₂₆H₂₉NO·C₆H₈O₇ especially to treat breast cancer or reduce the risk of its development or reoccurrence see nolvadex

tamoxifen

noun

Examples of tamoxifen in a Sentence

Word History

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Medical Definition

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