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
chromosomalplay \ˌkrō-mə-ˈsō-məl, -ˈzō-\ adjective
chromosomallyplay \-mə-lē\ adverb
Recent Examples of chromosome from the Web
Telomeres are the tips of chromosomes that protect DNA while it's being copied -- like the aglet at the end of a shoelace that prevents it from fraying.
Certain sequences cap the ends of chromosomes, safeguarding the information from being worn away when cells divide and replicate their DNA.
Humans have five such chromosomes and mice have just one.
Speaking of intersex: Born with sex characteristics such as genitals or chromosomes that do not fit the typical definitions of male or female.
These telomeres are a string of DNA proteins that rest at the end of a chromosome.
Telomeres, the protein caps on the ends of human chromosomes, are markers of aging and overall health.
Embryos with an abnormal number of chromosomes -- there should be 23 pairs -- often don't make it.
A small number of rodents have no Y chromosomes, yet are born as either females or males, not hermaphrodites.
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.
Origin and Etymology of chromosome
International Scientific Vocabulary
First Known Use: 1889See Words from the same year
CHROMOSOME Defined for English Language Learners
Definition of chromosome for English Language Learners
: the part of a cell that contains the genes which control how an animal or plant grows and what it becomes
CHROMOSOME Defined for Kids
Definition of chromosome for Students
: one of the rod-shaped or threadlike structures of a cell nucleus that contain genes and divide when the cell divides
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
chromosomal\ˌkrō-mə-ˈsō-məl, -ˈzō-\play adjective
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