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
Example Sentences
Recent Examples on the Web These are tumors that do not carry receptors for estrogen, progesterone, or human epidermal growth factor, typically targeted by such drugs as Herceptin or tamoxifen. 
Adam Feuerstein, STAT, 22 Apr. 2020 All participants were given standard hormone therapy (an aromatase inhibitor or tamoxifen) as well as a medication that shuts down the ovaries' production of estrogen. Samantha Lauriello, Health.com, 4 June 2019 All of the women were given standard hormonal therapy -- an aromatase inhibitor or tamoxifen -- plus a medication that shuts down the ovaries' production of estrogen. Amy Norton, CBS News, 3 June 2019 Hormone therapy with the drug tamoxifen is also common. Korin Miller, SELF, 13 Dec. 2018 Phyllis Laccetti, a participant in the study, took the hormonal therapy tamoxifen alone for five years after having a mastectomy in 2007 to treat her breast cancer, even though her doctor’s initial recommendation was to also receive chemotherapy. Peter Loftus, WSJ, 3 June 2018 Generally, after surgery, such patients receive endocrine therapy, such as tamoxifen, which is designed to block the cancer-spurring effects of hormones. Laurie Mcginley, Washington Post, 3 June 2018 Generally, after surgery, such patients receive endocrine therapy, such as tamoxifen, which is designed to block the cancer-spurring effects of hormones. Laurie Mcginley, BostonGlobe.com, 3 June 2018 And a Tufts University study, published earlier this year, showed that soy consumption isn’t problematic for women who currently have breast cancer and doesn’t make cancer treatment drugs like tamoxifen less effective. Marygrace Taylor, Good Housekeeping, 17 May 2017 See More
Adam Feuerstein, STAT, 22 Apr. 2020 All participants were given standard hormone therapy (an aromatase inhibitor or tamoxifen) as well as a medication that shuts down the ovaries' production of estrogen. Samantha Lauriello, Health.com, 4 June 2019 All of the women were given standard hormonal therapy -- an aromatase inhibitor or tamoxifen -- plus a medication that shuts down the ovaries' production of estrogen. Amy Norton, CBS News, 3 June 2019 Hormone therapy with the drug tamoxifen is also common. Korin Miller, SELF, 13 Dec. 2018 Phyllis Laccetti, a participant in the study, took the hormonal therapy tamoxifen alone for five years after having a mastectomy in 2007 to treat her breast cancer, even though her doctor’s initial recommendation was to also receive chemotherapy. Peter Loftus, WSJ, 3 June 2018 Generally, after surgery, such patients receive endocrine therapy, such as tamoxifen, which is designed to block the cancer-spurring effects of hormones. Laurie Mcginley, Washington Post, 3 June 2018 Generally, after surgery, such patients receive endocrine therapy, such as tamoxifen, which is designed to block the cancer-spurring effects of hormones. Laurie Mcginley, BostonGlobe.com, 3 June 2018 And a Tufts University study, published earlier this year, showed that soy consumption isn’t problematic for women who currently have breast cancer and doesn’t make cancer treatment drugs like tamoxifen less effective. Marygrace Taylor, Good Housekeeping, 17 May 2017 See More Word History
Etymology
probably by recombination & alteration of trans-, oxy, and clomiphene
First Known Use
1972, in the meaning defined above
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