external anal sphincter(redirected from Sphincter ani externus muscle)
Also found in: Wikipedia.
ex·ter·nal a·nal sphinc·ter[TA]
a fusiform ring of striated muscular fibers surrounding the anus, attached posteriorly to the coccyx and anteriorly to the central tendon of the perineum; it is subdivided, often indistinctly, into a subcutaneous part, a superficial part, and a deep part for descriptive purposes.
Farlex Partner Medical Dictionary © Farlex 2012