se·​nil·​i·​ty | \ si-ˈni-lə-tē also se- \

Definition of senility

: the quality or state of being senile : the physical and mental decline associated with old age especially : the deterioration of cognitive functioning associated with old age

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Examples of senility in a Sentence

with his increasing senility, Granddad is beginning to have more and more senior moments

Recent Examples on the Web

My grandmother had descended into senility without me. Keith Gessen, Longreads, "My Brother Comes to Moscow," 10 July 2018 People pointed to Magic Johnson, Dave DeBusschere, Spencer Haywood and others – who had remarkable NBA careers and wondered if senility had finally caught up with SOS. Mick Mccabe, Detroit Free Press, "Class C champ Detroit Edison's Brandon Neely lives with memory of gun shot," 25 Mar. 2018 Trump and his allies are correct that Reagan’s critics accused him of senility in office. Jonathan Chait, Daily Intelligencer, "Why Republicans Love Dumb Presidents," 10 Jan. 2018 Your 18-year-old cat could have health problems resulting in pain or could have a cognitive dysfunction, like senility or dementia., "To drive or fly pets on a long-distance move," 24 May 2017 André’s ego is too large and impregnable to be deflated by senility. Ben Brantley, New York Times, "Review: ‘The Father’ Examines the Lion’s Mind in Winter," 14 Apr. 2016 I was inclined to dismiss his fractious behavior as the first sign of senility. Jeffrey Frank, The New Yorker, "Ike, Ford, and a Lost Voice in Supreme Court Nominations," 16 Feb. 2016 Few ideas in biology have been more fixed than the doctrine that people are born with a finite number of brain cells and go downhill from there, neuronwise, all the way to senility. Esquire, "More of The Esquire 21," 29 Jan. 2007

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'senility.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of senility

1791, in the meaning defined above

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Statistics for senility

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Time Traveler for senility

The first known use of senility was in 1791

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More Definitions for senility


se·​nil·​i·​ty | \ si-ˈnil-ət-ē also se-\
plural senilities

Medical Definition of senility

: the quality or state of being senile

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More from Merriam-Webster on senility

Rhyming Dictionary: Words that rhyme with senility

Thesaurus: All synonyms and antonyms for senility

Spanish Central: Translation of senility

Nglish: Translation of senility for Spanish Speakers

Britannica English: Translation of senility for Arabic Speakers

Comments on senility

What made you want to look up senility? Please tell us where you read or heard it (including the quote, if possible).


a servile follower or underling

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