miosis
Small / Constricted Pupil
Plain-language definition
Abnormal constriction of the pupil. A miotic pupil on one side is a key sign of Horner syndrome.
Where this term comes up
“Pilocarpine is a cholinergic (parasympathomimetic) eye drop that causes the pupil to constrict (miosis) and opens the drainage angle of the eye.”
Medication · Pilocarpine
“The classic triad is a smaller pupil (miosis), mild droopy eyelid (ptosis), and reduced facial sweating (anhidrosis).”
Condition · Horner Syndrome
“Pupil smaller (miosis)”
Symptom · Unequal Pupil Size (Anisocoria)
- Category
- Condition, finding, or disease process
- Also written as
- No alternate forms listed.
Pathology terms describe diseases, tissue changes, exam findings, or complications that can affect vision or eye comfort.
Related glossary terms
- MRI
Magnetic Resonance Imaging
- anisocoria
Pupils of Unequal Size
- ptosis
Drooping Upper Eyelid
- aneurysm
Vessel Bulge
- anhidrosis
Absent Sweating
- ischemia
Reduced Blood Supply
A note on medical context
A glossary definition can explain a word, but it cannot tell you whether a symptom or test result is serious. If this term came from an article, use the full article and your clinician's guidance for context.