Simple Definition of senile

from our Learner's Dictionary

senile

adjective

: showing a loss of mental ability (such as memory) in old age
a senile man in his eighties
Her mother is becoming/getting/going senile.

Cite this Entry

“Senile.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/senile. Accessed 23 Jun. 2026.

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