chro·​mo·​some | \ ˈkrō-mə-ˌsōm How to pronounce chromosome (audio) , -ˌzōm\

Definition of chromosome

: any of the rod-shaped or threadlike DNA-containing structures of cellular organisms that are located in the nucleus of eukaryotes, are usually ring-shaped in prokaryotes (such as bacteria), and contain all or most of the genes of the organism also : the genetic material of a virus — compare chromatin

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Other Words from chromosome

chromosomal \ ˌkrō-​mə-​ˈsō-​məl How to pronounce chromosomal (audio) , -​ˈzō-​ \ adjective
chromosomally \ ˌkrō-​mə-​ˈsō-​mə-​lē How to pronounce chromosomally (audio) , -​ˈzō-​ \ adverb

Examples of chromosome in a Sentence

Recent Examples on the Web

Practitioners measure things like telomeres—the protective caps on chromosomes that supposedly reveal one’s biological age—to locate the source of an ailment or those last stubborn pounds. Jancee Dunn, Vogue, "The Future of Dieting Is Here—And it Has Nothing to do With Calorie Counting," 29 Oct. 2018 The Down/Alzheimer’s link may center around having an extra copy of chromosome 21, which is what brings about characteristics of Down syndrome. Korin Miller, SELF, "10 Facts About Alzheimer's Disease You Should Know," 28 Sep. 2018 The vast majority of our DNA—the chromosomes in the nucleus of each cell—is just what you’d expect: a mix of genetic material from both mother and father. Cathleen O'grady, Ars Technica, "Plot twist: Mitochondrial DNA can come from both parents," 28 Nov. 2018 The genomic structure is the way that genes are arranged on chromosomes in each species. Darren Griffin, Scientific American, "Jurassic World: Can We Really Resurrect a Dinosaur?," 6 June 2018 The condition is caused by a DNA glitch in chromosome 15. Shelley Levitt, Woman's Day, "These 4 Inspirational Women Went to Great Lengths for Their Kids," 4 Dec. 2018 Terry Jo, who worked as a midwife, had suffered two miscarriages after the birth of her daughters, but the results of her amniocentesis and chromosome testing had come back normal. Shelley Levitt, Woman's Day, "These 4 Inspirational Women Went to Great Lengths for Their Kids," 4 Dec. 2018 These molecular interactions leave chemical marks on the chromosomes passed on to different lines of cells in the body, explaining why a brain cell cannot be simply reprogrammed into a kidney cell or vice versa. John Hawks, WSJ, "‘Lamarck’s Revenge’ Review: Inheriting the Wrong Ideas," 16 Aug. 2018 The chromosomes naturally swap DNA during meiosis, and during those exchanges the cell only allows HDR. Jon Cohen, Science | AAAS, "‘Gene drive’ passes first test in mammals, speeding up inheritance in mice," 10 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'chromosome.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of chromosome

1889, in the meaning defined above

History and Etymology for chromosome

borrowed from German Chromosom, from chromo- chromo- + -som -some entry 3

Note: The term Chromosom was first suggested by the German anatomist Heinrich Wilhelm Gottfried von Waldeyer-Hartz in "Ueber Karyokinese und ihre Beziehungen zu den Befruchtungsvorgängen," Archiv für mikroskopische Anatomie, Band 23 (1888), p. 27: "In ester Linier möchte ich mir jedoch den Vorschlag erlauben, diejenigen Dinge, welche soeben mit Boveri als 'chromatische Elemente' bezeichnet wurden, an denen sich einer der wichtigsten Akten der Karyokinese, die Flemming'sche Längsteilung vollzieht, mit einem besonderen terminus technicus 'Chromosomen' zu belegen. Der Name 'primäre Schleifen' passt nicht, da wir bei weitem nicht immer eine Schleifenform für diese Dinge haben. 'Chromatische Elemente' ist zu lang. Andererseits sind sie so wichtig, dass ein besonderer kürzerer Name wünschenswerth erscheint. Plattne… gebraucht den Ausdruck 'Karyosomen'; da dieser aber zu sehr an Kernkörperchen erinnert, dürfte eine andere Bezeichnung vorzuziehen sein. Ist die von mir vorgeschlagene praktisch verwendbar, so wird sie sich wohl einbürgern, sonst möge sie bald der Vergessenheit anheimfallen." ("In the first place I must allow myself to suggest a new technical term, 'chromosomes,' for those things which have been designated by Boveri 'chromatic elements,' at which one of the most important acts of karyokinesis, Flemming's longitudinal splitting, is carried out. The name 'primary loops' is not suitable, since it is by no means the case that these things always have the form of a loop. 'Chromatic elements' is too long. On the other hand, they are so important that a special shorter name seems desirable. Plattner uses the expression 'karyosomes,' but as this too readily brings to mind nucleoli, another name is to be preferred. If the name I propose is serviceable, it will become customary, otherwise it will soon pass into oblivion.")

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Last Updated

3 Mar 2019

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Time Traveler for chromosome

The first known use of chromosome was in 1889

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More Definitions for chromosome



English Language Learners Definition of chromosome

: the part of a cell that contains the genes which control how an animal or plant grows and what it becomes


chro·​mo·​some | \ ˈkrō-mə-ˌsōm How to pronounce chromosome (audio) \

Kids Definition of chromosome

: one of the rod-shaped or threadlike structures of a cell nucleus that contain genes and divide when the cell divides


chro·​mo·​some | \ ˈkrō-mə-ˌsōm, -ˌzōm How to pronounce chromosome (audio) \

Medical Definition of chromosome

: any of the usually linear bodies of the cell nucleus of eukaryotic organisms, the usually circular bodies of prokaryotic organisms (as bacteria), or especially in some schools of molecular biology the genomes of DNA viruses (as bacteriophages) that take up basophilic stains and contain most or all of the genes of the organism both the chromosomes of cells and those of viruses can duplicate only in the complex environment of a living cell— J. D. Watson an episome, an element that may exist as a free circular plasmid, or that may become integrated into the bacterial chromosome as a linear sequence— Benjamin Lewin

Other Words from chromosome

chromosomal \ ˌkrō-​mə-​ˈsō-​məl, -​ˈzō-​ How to pronounce chromosomal (audio) \ adjective
chromosomally \ -​mə-​lē How to pronounce chromosomally (audio) \ adverb

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More from Merriam-Webster on chromosome

Spanish Central: Translation of chromosome

Nglish: Translation of chromosome for Spanish Speakers

Britannica English: Translation of chromosome for Arabic Speakers Encyclopedia article about chromosome

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What made you want to look up chromosome? Please tell us where you read or heard it (including the quote, if possible).


to corrupt or become corrupted

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