re·​lax·​in | \ri-ˈlak-sən \

Definition of relaxin 

: a sex hormone of the corpus luteum that facilitates birth by causing relaxation of the pelvic ligaments

Examples of relaxin in a Sentence

Recent Examples on the Web

For instance, during pregnancy, your body produces a hormone called relaxin that relaxes the ligaments in your pelvis. Korin Miller, SELF, "The Surprising Reasons Why It's So Hard to Get Back Into Working Out After Pregnancy," 11 May 2018 Wolf pregnancies, for example, can be tested using commercial dog pregnancy kits that detect a hormone called relaxin. Sarah Zhang, The Atlantic, "It's Really Hard to Know When a Zoo Animal Is Pregnant," 15 Dec. 2017 Her feet and hips were more mobile, too -- a consequence of a hormone called relaxin which loosens ligaments and tendons in preparedness for giving birth. Aimee Lewis, CNN, "Can Serena Williams return to the top of tennis after giving birth?," 22 May 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'relaxin.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of relaxin

1930, in the meaning defined above

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Time Traveler for relaxin

The first known use of relaxin was in 1930

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More Definitions for relaxin


re·​lax·​in | \ri-ˈlak-sən \

Medical Definition of relaxin 

: a polypeptide sex hormone of the corpus luteum that facilitates birth by causing relaxation of the pelvic ligaments

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a soft lustrous wool fabric with mohair

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