mi·o·sis

also my·o·sis (mī-ō′sĭs)

n. pl. mi·o·ses (-sēz) also my·o·ses

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.

[Greek mūein, to close the eyes + -osis.]

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

miosis

(maɪˈəʊsɪs) or

myosis

n, pl -ses (-siːz)

1. (Pathology) excessive contraction of the pupil of the eye, as in response to drugs

2. (Biology) a variant spelling of meiosis¹

[C20: from Greek muein to shut the eyes + -osis]

miotic, myotic adj, n

Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

mi•o•sis

or my•o•sis

(maɪˈoʊ sɪs)

n.

excessive constriction of the pupil of the eye.

Compare mydriasis.

[1810–20; variant of myosis < Greek mý(ein) to shut (the eyes) + -osis]

miosis, myosis

abnormal constriction of the pupil of the eye, caused by drugs or illness. Cf. mydriasis. — miotic, myotic, adj.

See also: Eyes

ThesaurusAntonymsRelated WordsSynonymsLegend:

Noun	1.	miosis - (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 genetic science, genetics - the branch of biology that studies heredity and variation in organisms anaphase - the stage of meiosis or mitosis when chromosomes move toward opposite ends of the nuclear spindle cell division, cellular division - the process in reproduction and growth by which a cell divides to form daughter cells cytokinesis - organic process consisting of the division of the cytoplasm of a cell following karyokinesis bringing about the separation into two daughter cells karyokinesis - organic process consisting of the division of the nucleus of a cell during mitosis or meiosis metaphase - the second stage of meiosis nondisjunction - meiosis in which there is a failure of paired homologous chromosomes to separate; results in an abnormal number of chromosomes in the daughter cells prophase - the first stage of meiosis segregation - (genetics) the separation of paired alleles during meiosis so that members of each pair of alleles appear in different gametes telophase - the final stage of meiosis when the chromosomes move toward opposite ends of the nuclear spindle
	2.	miosis - 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 inborn reflex, innate reflex, instinctive reflex, physiological reaction, reflex, reflex action, reflex response, unconditioned reflex - an automatic instinctive unlearned reaction to a stimulus

Translations

mi·o·sis

n. miosis, contracción excesiva de la pupila.