chromosome number

American

noun

Genetics.

the characteristic number of chromosomes contained in the cell nucleus of a given species.

chromosome number British

noun

the number of chromosomes present in each somatic cell, which is constant for any one species of plant or animal. In the reproductive cells this number is halved See also diploid haploid

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of chromosome number

First recorded in 1905–10

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

One of the earliest warning signs in this process is the presence of chromosomal abnormalities, which include changes in chromosome number or structure.

From Science Daily • Mar. 10, 2026

Genomic sequencing also revealed that D. catalonica has a haploid chromosome number of four autosomes plus one X chromosome, while D. tilosensis has six autosomes and one X chromosome.

From Science Daily • Nov. 2, 2025

The process of meiosis reduces the chromosome number by half.

From Textbooks • Jun. 9, 2022

Chromosome disorders can be divided into two categories: abnormalities in chromosome number and chromosome structural rearrangements.

From Textbooks • Apr. 25, 2013

Occasionally this is attached to another so that the chromosome number remains the normal 46.

From "Silent Spring" by Rachel Carson

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023