sphincter (n.)youdaoicibaDictYouDict[sphincter 词源字典]
1570s, from Middle French sphincter, from Late Latin sphincter "contractile muscle," from Greek sphinkter "band, lace, anything that binds tight," from sphingein "to squeeze, bind," of unknown origin. First used in anatomical sense by Galen. There are several in the body; the one usually meant is the sphincter ani.[sphincter etymology, sphincter origin, 英语词源]