platysmata

Main Entry: pla·tys·ma
Pronunciation: pl&-'tiz-m&
Function: noun
Inflected Form: plural pla·tys·ma·ta /-m&t-&/ also pla·tys·mas
: a broad thin layer of muscle that is situated on each side of the neck immediately under the superficial fasciabelonging to the group of facial muscles, that is innervated by the facial nerve, and that draws the lower lip and the corner of the mouth to the side and down and when moved forcefully expands theneck and draws its skin upward —pla·tys·mal /-m&l/ adjective

platysma pla·tys·ma (plə-tĭz'mə)
n. pl. pla·tys·mas or pla·tys·ma·ta (-mə-tə)
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.