9 letters · 16 points in Scrabble
noun a ring of muscle that contracts to close an opening
originEtymology tree Late Latin sphinctērlbor. English sphincter Learned borrowing from Late Latin sphinctēr (“the muscle of the anus”), from Ancient Greek σφῐγκτήρ (sphĭnktḗr, “lace, band; contractile muscle”), ultimately of Pre-Greek origin. Possibly related to sphinx (“the strangler”).
Etymology from Wiktionary, CC BY-SA 3.0