from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Constriction of the pupil of the eye, resulting from a normal response to an increase in light or caused by certain drugs or pathological conditions.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Contraction of the pupil of the eye.
from The Century Dictionary and Cyclopedia
- n. Diminution.
- n. In cytology, the reduction-process in organisms, including mitapsis (or synapsis) and the subsequent heterotypic and homotypic divisions. This process results in reducing to one half the number of chromosomes in the nuclei. Farmer and Moore. Improperly spelled maiosis.
- n. Used by error or substitution for myosis.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. (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)
- n. reflex contraction of the sphincter muscle of the iris in response to a bright light (or certain drugs) causing the pupil to become smaller
Greek mūein, to close the eyes + -osis.(American Heritage® Dictionary of the English Language, Fourth Edition)
From Ancient Greek μύειν (mūein, "to close the eyes") + -osis. (Wiktionary)