What does centromere mean?
A centromere is the specialized, constricted region of a chromosome that holds its two identical halves — the sister chromatids — together until they separate during cell division. Visible under a microscope as a pinched waist on the chromosome, it serves as the assembly site for the kinetochore, the protein structure to which spindle fibres attach. When a cell divides, these fibres pull on the centromeres so that each daughter cell receives an accurate copy of the genetic material. Errors involving centromeres can lead to chromosomes being mis-segregated, a phenomenon linked to certain cancers and genetic disorders. The word derives from the Greek roots 'kentron' (sharp point, centre) and 'meros' (part), reflecting its position near the middle of many chromosomes. Though strictly a term of cytogenetics and molecular biology, the centromere appears widely in biology education and research writing, making it essential vocabulary for anyone studying heredity or cell division.
nounThe constricted region of a chromosome that joins its two sister chromatids and serves as the attachment point for spindle fibres during cell division.
- The constricted chromosomal region where the two sister chromatids are joined and to which spindle fibres attach during mitosis and meiosis.
"During mitosis, spindle fibres attach to the centromere and pull the sister chromatids toward opposite poles of the cell."
"Stains revealed a dark band marking the position of the centromere on each chromosome."
"Errors in centromere function can cause chromosomes to be distributed unevenly between daughter cells."
Regular plural formation; commonly used when discussing multiple chromosomes or comparing species.
"Human cells contain forty-six chromosomes, each with its own centromere."
Every one of your chromosomes has a single pinch-point called the centromere — without it, cell division would tear your genome apart.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of centromere
The word centromere was coined in the late nineteenth century by early cytologists studying chromosome behaviour under the microscope. It combines two Greek roots: 'kentron', meaning a sharp point or centre, which also gives us words like 'central' and 'centrifugal', and 'meros', meaning part, which appears in related terms such as 'polymer' and 'isomer'. The name reflects both the structure's typically central position on the chromosome and its role as a distinct structural component.
Related word forms
How centromere is actually used
A technical term used almost exclusively in genetics, cytology, and molecular biology; it rarely appears outside scientific or educational writing. The related adjective 'centromeric' describes DNA or features associated with the centromere.
Easily confused with centromere
A centromere sits in the middle region of a chromosome and anchors spindle fibres during division, whereas a telomere caps each end of a chromosome and protects it from degradation.