[ pluh-tiz-muh ]
/ pləˈtɪz mə /

noun, plural pla·tys·mas, pla·tys·ma·ta [pluh-tiz-muh-tuh] /pləˈtɪz mə tə/, Anatomy.

a broad, thin muscle on each side of the neck, extending from the upper part of the shoulder to the corner of the mouth, the action of which wrinkles the skin of the neck and depresses the corner of the mouth.

Origin of platysma

1685–95; < New Latin < Greek plátysma a plate, literally, something wide and flat, equivalent to platý(nein) to widen (derivative of platýs; see platy-) + -sma, variant of -ma resultative suffix Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for platysma

Medicine definitions for platysma

[ plə-tĭzmə ]

n. pl. pla•tys•mas

A platelike muscle in the neck extending to the lower face with origin from the subcutaneous layer and fascia covering the greater pectoral and deltoid muscles at the level of the first or second rib, with insertion to the mandible, the risorius muscle and platysma of the opposite side, with nerve supply from a branch of the facial nerve, and whose action depresses the lower lip and wrinkles the skin of the neck and the upper chest.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.