Mydriasis vs. Miosis

Mydriasisnoun

(medicine) The condition of having abnormally large and dilated pupils due to disease or drugs, particularly stimulants such as (meth)amphetamines, cocaine, etc.

Mydriasisnoun

A long-continued or excessive dilatation of the pupil of the eye.

Mydriasisnoun

reflex pupillary dilation as a muscle pulls the iris outward; occurs in response to a decrease in light or certain drugs

Mydriasis

Mydriasis is the dilation of the pupil, usually having a non-physiological cause, or sometimes a physiological pupillary response. Non-physiological causes of mydriasis include disease, trauma, or the use of drugs.

Miosisnoun

Contraction of the pupil of the eye.

Miosisnoun

(genetics) cell division that produces reproductive cells in sexually reproducing organisms; the nucleus divides into four nuclei each containing half the chromosome number (leading to gametes in animals and spores in plants)

Miosisnoun

reflex contraction of the sphincter muscle of the iris in response to a bright light (or certain drugs) causing the pupil to become smaller

Miosis

Miosis, or myosis, is excessive constriction of the pupil. The term is from Ancient Greek μύειν mūein, .