What does apoptosis mean?
Apoptosis is the biological process by which cells deliberately destroy themselves as part of normal growth, development, or maintenance — a phenomenon scientists commonly call programmed cell death. Unlike necrosis, which is messy cell death caused by injury or infection and which spills damaging contents into surrounding tissue, apoptosis is orderly and contained: the shrinking cell fragments neatly and is swiftly absorbed by its neighbours, leaving no inflammation behind. The process is essential to life. It sculpts organs during embryonic development, prunes surplus neurons in the developing brain, removes the webbing between growing fingers and toes, and eliminates damaged or infected cells that might otherwise become harmful. Its failure, however, can be catastrophic: cancer cells famously resist apoptosis and thereby achieve immortality, while excessive apoptosis contributes to degenerative conditions. Because of this dual role, apoptosis is one of the most intensively studied processes in modern biomedical research.
nounThe death of cells that occurs as a normal, genetically programmed part of an organism's growth or development, in which the cell shrinks and is broken down without releasing harmful contents. It is often described as 'programmed cell death'.
- Biology: the process of genetically programmed cell death, in which a cell systematically dismantles itself and is engulfed by neighbouring cells without triggering inflammation.
"During embryonic development, apoptosis removes the webbing between the fingers, allowing separate digits to form."
"Cancer cells are dangerous in part because they evade apoptosis, continuing to divide when they should die."
"In response to irreparable DNA damage, the cell initiates apoptosis as a protective measure for the organism."
Rarely used; apoptosis is almost always treated as an uncountable noun referring to the general process rather than to individual occurrences.
"The study compared apoptoses across several different tissue types."
Your body kills billions of its own cells every single day — quietly, cleanly, and on purpose. That process is called apoptosis.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of apoptosis
The term derives from the ancient Greek 'apóptōsis', meaning 'falling off' or 'dropping off' — from 'apo-' ('away from') plus 'ptōsis' ('a falling'), the same root that gives English 'ptosis' for drooping eyelids. The word was chosen by analogy with leaves falling naturally from trees, evoking the idea of cells dropping away as part of a healthy cycle. It was adopted into modern scientific usage in 1972, when John Kerr, Andrew Wyllie, and Alastair Currie introduced it in their landmark paper describing this distinct mode of cell death.
Related word forms
How apoptosis is actually used
Strictly scientific and medical register; rarely used outside biology, medicine, and related research contexts. The second 'p' is traditionally silent in careful British usage (reflecting the Greek), though pronouncing it has become increasingly common; American speakers typically pronounce both p's.
Easily confused with apoptosis
Apoptosis is a controlled, orderly form of programmed cell death that does not damage surrounding tissue, whereas necrosis is uncontrolled cell death caused by injury or disease that triggers inflammation.