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Glite Dictionary
musculus sphincter pupillae

musculus sphincter pupillae

8.9
A ring of muscle in the eye that makes the pupil smaller in bright light
  • noun
  • /ˈmʌskjələs ˈsfɪŋktər pjuˈpɪleɪ/
  • Specialized
translation icon : músculo esfínter de la pupila
  • The musculus sphincter pupillae contracts in bright light to reduce the size of the pupil.

Examples

  • Damage to the musculus sphincter pupillae can cause abnormal pupil responses.

  • Certain medications affect the musculus sphincter pupillae, leading to changes in pupil diameter.

  • The musculus sphincter pupillae controls the size of the pupil.

  • When light enters the eye, the musculus sphincter pupillae contracts.

  • The musculus sphincter pupillae contracts in response to bright light, helping to protect the retina.

  • In situations of low light, the musculus sphincter pupillae relaxes, allowing the pupil to widen.

  • Doctors assess the function of the musculus sphincter pupillae during eye examinations to check for neurological issues.

Synonyms

pupillary sphincter
vsmusculus sphincter pupillae
  • Specialized
8.9

A ring of muscle in the coloured part of the eye that makes the pupil smaller

is the same meaning but uses a different anatomical phrasing

Surface Forms

musculus sphincter pupillae singular
musculi sphincter pupillae plural

Morphology

musculus + sphincter + pupillae

The term is a literal Latin anatomical name composed of 'musculus' (muscle) + 'sphincter' (a closing/regulating muscle) + 'pupillae' (of the pupil), so the meaning — the sphincter muscle of the pupil — is directly derivable from its parts. Latin-based anatomical nomenclature is widespread and parallels exist in many languages, making the composition transparently interpretable to learners who know the constituent elements.

Etymology

Musculus sphincter pupillae literally names the tiny muscle that tightens the pupil: musculus means 'muscle', sphincter is a 'tightener', and pupillae refers to the 'pupil'. Imagine a small ring squeezing the pupil like a belt, and that image explains why this muscle makes the pupil smaller in bright light.