progesterone

noun

pro·​ges·​ter·​one prō-ˈje-stə-ˌrōn 

: a female steroid sex hormone C₂₁H₃₀O₂ that is secreted by the corpus luteum to prepare the endometrium for implantation and later by the placenta during pregnancy to prevent rejection of the developing embryo or fetus

Examples of progesterone in a Sentence

Recent Examples on the Web

The drop in estrogen and progesterone directly and indirectly affects sleep, a phenomenon sometimes called hormonal insomnia. — Hanna Wickes, Fort Worth Star-Telegram, 17 July 2026

The widely used ‘Day 21’ progesterone test is based on a standard 28-day cycle that, in his view, does not reflect the variability of most menstrual cycles. — Matt Emma, USA Today, 14 July 2026

The symptoms can overlap because post-childbirth, estrogen and progesterone drop to their pre-pregnancy levels. — Theara Coleman, TheWeek, 13 July 2026

According to the outlet, Howlett said she and Julie Howlett had been married for four years and were both transitioning to female while taking estrogen and progesterone. — Stepheny Price, FOXNews.com, 2 July 2026

Word History

Etymology

blend of progestin and luteosterone (borrowed from German Luteosteron, from luteo- luteo- + -steron -sterone), both earlier names for progesterone

Note: The name resulted from a compromise between researchers associated with the earlier names, the American gynecologist Willard M. Allen and embryologist George Washington Corner, and the German biochemists Adolph Butenandt and Karl Heinrich Slotta. See W. M. Allen, A. Butenandt, G. W. Corner, and K. H. Slotta, "Nomenclature of Corpus Luteum Hormone," Nature, vol. 136, number 303 (September 1, 1935), p. 303.

First Known Use

1935, in the meaning defined above

Rhymes for progesterone

• aldosterone
• anticyclone
• hydrocodone
• testosterone
• acetone
• anglophone
• baritone
• bourguignon
• buspirone
• chaperon
• chaperone
• cobblestone

Kids Definition

progesterone

noun

pro·​ges·​ter·​one prō-ˈjes-tə-ˌrōn 

: a hormone that is produced by the corpus luteum and causes the uterus to change so that it provides a suitable environment for a fertilized egg

Medical Definition

progesterone

noun

pro·​ges·​ter·​one prō-ˈjes-tə-ˌrōn 

: a female steroid sex hormone C₂₁H₃₀O₂ that is secreted by the corpus luteum to prepare the endometrium for implantation and later by the placenta during pregnancy to prevent rejection of the developing embryo or fetus

Note: Synthetic steroids (such as progestins) that function similarly in the body are sometimes also referred to as progesterones.