risorius

(redirected from risorius muscle)
Also found in: Thesaurus, Medical, Encyclopedia.

risorius

(rɪˈzɔːrɪəs)
n
a facial muscle responsible for smiling
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
Rarely, if the injection is not performed properly, the risorius muscle may be paralyzed, leading to an asymmetric smile.
Just under the ear, she places an inverted triangle in white clay, the parotid, a salivary gland and, stretching from the parotid gland to the corner of the mouth, the thin risorius muscle (Fig 8), often called the Tip stretcher', widening the mouth and creating a sardonic expression.
Denervation of the orbicularis oculi muscle results in the inability of the patient to close the eye lids effectively, while denervation of the risorius muscle results in the limited retraction of the angle of mouth.