sphincter

noun

sphinc·​ter ˈsfiŋ(k)-tər 

: an annular muscle surrounding and able to contract or close a bodily opening

sphincteric

sfiŋ(k)-ˈter-ik 

adjective

Examples of sphincter in a Sentence

Recent Examples on the Web

Ginger can ease stomach pressure by reducing gas and bloating, which might otherwise cause the lower esophageal sphincter (LES) to open. —Lauren O'Connor, Health, 21 Oct. 2025

One reason is that the lower esophageal sphincter—a muscular valve between your esophagus and stomach—may weaken over time.4 This can result in stomach acid or food backing up into the esophagus, causing heartburn and irritation. —Fran Kritz, Verywell Health, 15 Sep. 2025

It was first described in 1985, caused by the sphincter's failure to relax and allow urine to pass, according to the Bladder and Bowel Community. —Alyce Collins, MSNBC Newsweek, 3 Aug. 2025

Plus, there are critical nerves that run alongside the prostate and are in charge of the sphincter muscle, which closes the bladder and keeps urine contained. —Angela Haupt, Time, 27 June 2025

Word History

Etymology

Late Latin, from Greek sphinktēr, literally, band, from sphingein to bind tight

First Known Use

1578, in the meaning defined above

Kids Definition

sphincter

noun

sphinc·​ter ˈsfiŋ(k)-tər 

: a ringlike muscle surrounding a body opening that is able to make the opening smaller or close it

Medical Definition

sphincter

noun

sphinc·​ter ˈsfiŋ(k)-tər 

: an annular muscle surrounding and able to contract or close a bodily opening see anal sphincter, cardiac sphincter, precapillary sphincter, pyloric sphincter

sphincteral

-t(ə-)rəl 

adjective