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mifepristone Syllabification: mi·fep·ri·stone
Pronunciation: /ˌmifəˈpristōn/

Definition of mifepristone in English:


A synthetic steroid that inhibits the action of progesterone, given orally in early pregnancy to induce abortion. Also called RU-486 ( trademark ).
Example sentences
  • The present study was planned to find a safe, simple and optimally effective regimen of mifepristone and misoprostol for abortion of pregnancy up to 63 days.
  • No studies have specifically compared mifepristone with levonorgestrel.
  • This medication has been shown to be effective for elective abortions and medical termination of pregnancy during the first trimester, leading to studies of the effect of mifepristone in term pregnancies.


1980s: probably from Dutch mifepriston, from mife- (representing aminophenol) + -pr- (representing propyl) + -ist- (representing estradiol) + -one.

Definition of mifepristone in:

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