norethisterone

== English == === Alternative forms === norethindrone (US) === Etymology === From nor- +‎ ethisterone. === Pronunciation === (Received Pronunciation) IPA(key): /nɔː.ɹɛˈθɪ.stə.ɹəʊn/ (General American) IPA(key): /ˌnɔɹ.əˈθɪ.stəˌɹoʊn/ === Noun === norethisterone (uncountable) (pharmacology) A synthetic steroid hormone, 19-nor-17α-ethynyltestosterone (C20H26O2), which has actions similar to those of progesterone and is used chiefly for contraception. === References === “norethisterone”, in Lexico, Dictionary.com; Oxford University Press, 2019–2022. “norethindrone”, in Merriam-Webster Online Dictionary, Springfield, Mass.: Merriam-Webster, 1996–present.