a ring-shaped muscle that relaxes or tightens to open or close a passage or opening in the body. examples are the anal sphincter (around the opening of the anus) and the pyloric sphincter (at the lower opening of the stomach).
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the cerebrum
the cerebellum
唾液腺.
the spinal cord
the perineum
the hipbone
脊髄.
the spinal cord
the spinal cord
a brain
a ganglion
a romance
名詞の変化形:
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