senescence
noun
se·nes·cence
si-ˈne-sᵊn(t)s 
1
: the state of being old : the process of becoming old or aging
The life of a mosquito—and this may be the only good news about the insect—is brutal and short. Roughly one in five die every day, and not from senescence.—
Gary Taubes
Gary TaubesUntil we're all brain patterns on computers, there are still forces that do not bend to our wants, including senescence and death.—John Hodgman
John Hodgman2
: permanent arrest of the cell cycle in which cell division ceases
Cells divide as tissues develop and regenerate, but they can only do so a limited number of times. Eventually they stop dividing and enter a state called cellular senescence.—Science
ScienceCellular senescence is well correlated with the shortening of telomeres to less than the size required to maintain the integrity of chromosomes.—Daniel A. Haber
Daniel A. Haber3
: the growth phase in a plant or plant part (such as a leaf) from full maturity to death
… healthy leaves progress from active photosynthesis through senescence.—B. N. Rock et al.
B. N. Rock et al.
Did you know?
Senescence can be traced back to Latin senex, meaning "old." Can you guess which other English words come from senex? Senile might (correctly) come to mind, as well as senior. But another one might surprise you: senate. This word for a legislative assembly dates back to ancient Rome, where the Senatus was originally a council of elders composed of the heads of patrician families. There's also the much rarer senectitude, which, like senescence, refers to the state of being old (specifically, to the final stage of the normal life span).
Examples of senescence in a Sentence
Recent Examples on the Web
In rich and poor countries alike, a coming wave of senescence stands to impose completely unfamiliar burdens on many societies.
—Nicholas Eberstadt, Foreign Affairs, 10 Oct. 2024
And these diseases that are appearing are associated with the underlying process of senescence — aging, the aging of our cells, tissues, organs and organ systems that is immutable.
—Sandee Lamotte, CNN, 7 Oct. 2024
Their most recent product to launch is the award-winning Omnipotent Concentrate, $520, which was one of the first skincare products in the mainstream beauty world to address a phenomenon called cellular senescence.
—Jessica Ourisman, Forbes, 4 Oct. 2024
Hydra vulgaris, under optimal lab conditions, can live for years—potentially even centuries—without showing signs of senescence (aging).
—Scott Travers, Forbes, 17 Sep. 2024
See all Example Sentences for senescence 
Examples are automatically compiled from online sources to
show current usage.
Read More
Opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
Send us feedback.
Nicholas Eberstadt, Foreign Affairs, 10 Oct. 2024
And these diseases that are appearing are associated with the underlying process of senescence — aging, the aging of our cells, tissues, organs and organ systems that is immutable.
—Sandee Lamotte, CNN, 7 Oct. 2024
Their most recent product to launch is the award-winning Omnipotent Concentrate, $520, which was one of the first skincare products in the mainstream beauty world to address a phenomenon called cellular senescence.
—Jessica Ourisman, Forbes, 4 Oct. 2024
Hydra vulgaris, under optimal lab conditions, can live for years—potentially even centuries—without showing signs of senescence (aging).
—Scott Travers, Forbes, 17 Sep. 2024
See all Example Sentences for senescence
Dictionary Entries Near senescence
Cite this Entry
“Senescence.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/senescence. Accessed 28 Nov. 2024.
Copy CitationMedical Definition
senescence
noun
se·nes·cence
si-ˈnes-ᵊn(t)s
1
: the state of being old : the process of becoming old or aging
Beyond determining the start and end of the reproductive lifespan and rates of fertility, consequences extend to the broad impact of hormonal exposure and epigenetic ageing on health and senescence more generally.—Ben Bar-Sadeh et al., Nature Reviews Endocrinology
Ben Bar-Sadeh et al., Nature Reviews Endocrinology2
: permanent arrest of the cell cycle in which cell division ceases
Somatic cells are programmed to undergo only a limited number of cell divisions, after which they enter a state called senescence. … Cellular senescence is well correlated with the shortening of telomeres to less than the size required to maintain the integrity of chromosomes.—Daniel A. Haber, ACP Medicine
Daniel A. Haber, ACP MedicineThe p53 tumour suppressor is activated by numerous stressors to induce apoptosis, cell cycle arrest, or senescence.—Stuart D. Tyner et al., Nature
Stuart D. Tyner et al., NatureLove words? Need even more definitions?
Merriam-Webster unabridged
Share