anal sphincter
noun
: either of two sphincters controlling the closing of the anus:
a
: an outer sphincter of striated muscle extending from the coccyx to the central tendinous part of the perineum and surrounding the anus immediately beneath the skin
called also external anal sphincter, sphincter ani externus
b
: an inner sphincter formed by thickening of the circular smooth muscle of the rectum
called also internal anal sphincter, sphincter ani internus
Dictionary Entries Near anal sphincter
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“Anal sphincter.” Merriam-Webster.com Medical Dictionary, Merriam-Webster, https://www.merriam-webster.com/medical/anal%20sphincter. Accessed 29 Nov. 2024.
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