Definition of "progestin" [progestin]

• A natural or synthetic progestational substance that mimics some or all of the actions of progesterone. (noun)
• A crude hormone of the corpus luteum from which progesterone can be isolated in pure form. No longer in scientific use. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "One of the acting ingredients in almost every oral contraceptive on the market is a hormone called progestin, which works in combination with estrogen to both prevent the egg from dropping and to prevent sperm from moving into the uterus."
• "Drospirenone is a type of female sex hormone called a progestin."
• "Now, estrogen works great when it gets paired up with, or balanced by, another ovarian messenger called progestin, which gets released from the egg sac called a corpus luteum after the follicle ships out its egg."