chromosome

noun

chro·​mo·​some ˈkrō-mə-ˌsōm 

-ˌzōm

: 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

chromosomal

ˌkrō-mə-ˈsō-məl 

-ˈzō-

adjective

chromosomally

ˌkrō-mə-ˈsō-mə-lē 

-ˈzō-

adverb

Examples of chromosome in a Sentence

Recent Examples on the Web

Seattle Storm co-owner Celeste Keaton was suspended and fined by the WNBA after two teenage girls wearing shirts depicting XX and XY chromosomes said Keaton cursed at them. — Devon Henderson, New York Times, 2 Aug. 2026

The cognitive load, the weight of accountability and the necessary professional sacrifices do not change based on a chromosome. — Alexandra Kharazi, Forbes.com, 31 July 2026

Notably, the team identified one mammoth from Russia’s Wrangel Island that was neither biologically female (with XX chromosomes) nor biologically male (with XY chromosomes). — Laura Baisas, Popular Science, 30 July 2026

The genetic counselor explained that Griffin had the Uniparental disomy (UPD) genotype, in which both copies of a chromosome pair come from one parent. — Sara Belcher, PEOPLE, 19 July 2026

Word History

Etymology

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.")

First Known Use

1889, in the meaning defined above

Phrases Containing chromosome

• chromosome number
• lampbrush chromosome
• sex chromosome
• X chromosome
• Y chromosome

Rhymes for chromosome

• acrosome
• aerodrome
• catacomb
• centrosome
• cytochrome
• hippodrome
• honeycomb
• liposome
• meerschaum
• metronome
• microtome
• monochrome

Kids Definition

chromosome

noun

chro·​mo·​some ˈkrō-mə-ˌsōm 

-ˌzōm

: one of the rod-shaped or threadlike DNA-containing bodies of a cell nucleus that contain all or most of the genes of an organism and can be seen especially during cell division

chromosomal

ˌkrō-mə-ˈsō-məl 

-ˈzō-

adjective

Medical Definition

chromosome

noun

chro·​mo·​some ˈkrō-mə-ˌsōm, -ˌzōm 

: 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 (as bacteria), and contain all or most of the genes of the organism

also : the genetic material of a virus

chromosomal

ˌkrō-mə-ˈsō-məl, -ˈzō- 

adjective

chromosomally

-mə-lē 

adverb