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Noun: miosis (mioses)  mI'ow-sis
  1. (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)
    - meiosis, reduction division
  2. Reflex contraction of the sphincter muscle of the iris in response to a bright light (or certain drugs) causing the pupil to become smaller
    - light reflex, pupillary reflex, myosis

Derived forms: mioses

Type of: cell division, cellular division, inborn reflex, innate reflex, instinctive reflex, physiological reaction, reflex, reflex action, reflex response, unconditioned reflex

Encyclopedia: Miosis