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Synonyms

senescent

American  
[si-nes-uhnt] / sɪˈnɛs ənt /

adjective

  1. growing old; aging.

  2. Cell Biology. (of a cell) no longer capable of dividing but still alive and metabolically active.


senescent British  
/ sɪˈnɛsənt /

adjective

  1. growing old

  2. characteristic of old age

"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

Other Word Forms

  • senescence noun
  • unsenescent adjective

Etymology

Origin of senescent

First recorded in 1650–60; from Latin senēscent- (stem of senēscēns ) present participle of senēscere “to grow old,” equivalent to sen- “old” + -ēscent- -escent

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.

As the body ages, it accumulates senescent cells, which no longer divide but also do not die off.

From Science Daily • Jan. 3, 2026

"Our hope is that senotherapy, which involves using medications to remove senescent, or aging cells, could potentially minimize the need for surgery and/or improve outcomes after surgery."

From Science Daily • Dec. 25, 2025

More work will be needed to find aptamers that can reliably detect senescent cells in human tissue.

From Science Daily • Dec. 14, 2025

"Future studies may extend the approach to applications related to senescent cells in human disease."

From Science Daily • Dec. 14, 2025

In one thin arm, threaded with veins in a kind of senescent bas-relief, was a basket.

From "The Great Santini" by Pat Conroy