mitosis

American  

[mahy-toh-sis] / maɪˈtoʊ sɪs /

noun

Cell Biology.

1. the usual method of cell division, characterized typically by the resolving of the chromatin of the nucleus into a threadlike form, which condenses into chromosomes, each of which separates longitudinally into two parts, one part of each chromosome being retained in each of two new cells resulting from the original cell.

---

mitosis British  

/ maɪˈtəʊsɪs, mɪ-, mɪ-, maɪˈtɒtɪk /

noun

1. a method of cell division, in which the nucleus divides into daughter nuclei, each containing the same number of chromosomes as the parent nucleus Compare prophase metaphase anaphase telophase meiosis

---

mitosis Scientific  

/ mī-tō′sĭs /

1. The process in cell division in eukaryotes in which the nucleus divides to produce two new nuclei, each having the same number and type of chromosomes as the original. Prior to mitosis, each chromosome is replicated to form two identical strands (called chromatids). As mitosis begins, the chromosomes line up along the center of the cell by attaching to the fibers of the cell spindle. The pairs of chromatids then separate, each strand of a pair moving to an opposite end of the cell. When a new membrane forms around each of the two groups of chromosomes, division of the nucleus is complete. The four main phases of mitosis are prophase, metaphase, anaphase, and telophase.

2. Compare meiosis

---

mitosis Cultural  

1. Division of a single cell into two identical “daughter” cells. Each daughter cell has an identical number of chromosomes as the parent cell. Mitosis begins when the DNA in the parent cell replicates itself; it ends with two cells having the same genes (see genetics). Most cells in the human body, and all single-celled organisms, reproduce through mitosis. (Compare meiosis.)

---

Closer Look

Mitosis is the process by which the nucleus divides in eukaryotic organisms, producing two new nuclei that are genetically identical to the nucleus of the parent cell. diamf3 It occurs in cell division carried on by human somatic cells—the cells used for the maintenance and growth of the body. These cells have two paired sets of 23 chromosomes, or 46 chromosomes in total. (Cells with two sets of chromosomes are called diploid.) Before cell division occurs, the genetic material in each chromosome is duplicated as part of the normal functioning of the cell. Each chromosome then consists of two chromatids, identical strands of DNA. When a cell undergoes mitosis, the chromosomes condense into 46 compact bodies. The chromatids then separate, and one chromatid from each of the 46 chromosomes moves to each side of the cell as it prepares to divide. The chromatids form the chromosomes of the daughter cells, so that each new cell has 46 chromosomes, (two complete sets of 23) just like the parent cell. While both mitosis and meiosis refer properly to types of nuclear division, they are often used as shorthand to refer to the entire processes of cell division themselves. When mitosis and meiosis are used to refer specifically to nuclear division, they are often contrasted with cytokinesis, the division of the cytoplasm.

Other Word Forms

• intermitotic
  adjective
• mitotic
  adjective
• mitotically
  adverb

Etymology

Origin of mitosis

First recorded in 1885–90; from Greek mít(os) “thread” + -osis

Explanation

If you’re in biology class studying the way cells divide, then you’re probably learning about mitosis. Mitosis is a process of cell division in which the parent cell makes two new daughter cells, each with the same number of chromosomes as the parent. To do this, it goes through several different phases to divide and then rebuild the chromosomes. The word mitosis comes from the Greek word for "thread."

Example Sentences

Perhaps that’s the next phase of Coachella’s mitosis: Weekend 1 determines how Coachella is seen, and Weekend 2 is where that attention is extended, maybe even reshaped.

From Los Angeles Times • Apr. 26, 2026

Using a powerful, high-resolution genome mapping method, the team found that small 3D loops -- connections between regulatory DNA elements and genes -- remain intact even during cell division, a stage known as mitosis.

From Science Daily • Oct. 24, 2025

Using their technique, the researchers also confirmed that larger structures such as A/B compartments and TADs do disappear during mitosis, as had been seen before.

From Science Daily • Oct. 24, 2025

Many of these loops allow genes to interact with distant regulatory regions -- sometimes millions of base pairs apart -- while others form during mitosis to pack chromosomes tightly.

From Science Daily • Oct. 24, 2025

The centrioles, which hoist the microtubules on which chromosomes are strung for mitosis, are similar separate creatures; when not busy with mitosis, they become the basal bodies to which cilia are attached.

From "The Lives of a Cell" by Lewis Thomas