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

For me, yelling happened the most in the luteal phase of my menstrual cycle, when estrogen and progesterone are both at their lowest. —Simone Sauter, Parents, 29 Nov. 2025

Declining reproductive hormones Menopause occurs when the ovaries gradually produce less estrogen and progesterone, hormones that help regulate the menstrual cycle. —Akshay Syal, NBC news, 27 Nov. 2025

Easy@Home PdG Test Strips At-home urine test strips that detect the progesterone metabolite (PdG). —Adam Mills, MSNBC Newsweek, 26 Nov. 2025

In August, Mayci shared a video of Jacob administering a PIO (progesterone in oil) shot to her. —Jane Lacroix, PEOPLE, 14 Nov. 2025

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
• testosterone
• acetone
• anglophone
• baritone
• bourguignon
• buspirone
• chaperon
• chaperone
• cobblestone
• collarbone

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.