Sphincter Muscle (Noun)
Meaning
A ring of muscle that contracts to close an opening.
Classification
Nouns denoting body parts.
Examples
- The sphincter muscle around the anus tightens to prevent the release of feces.
- When you feel the urge to urinate, the internal urethral sphincter muscle relaxes, allowing urine to flow out.
- The eye's sphincter muscle controls the size of the pupil by constricting or dilating it.
- A circular layer of smooth sphincter muscle encircles the iris to regulate light entry.
- Damage to the external anal sphincter muscle can cause incontinence or leakage of stool.