From Longman Dictionary of Contemporary Englishsenilese‧nile /ˈsiːnaɪl/ adjective MIMENTALLY ILLmentally confused or behaving strangely, because of old age a senile old man She worries about going senile. —senility /sɪˈnɪləti/ noun [uncountable]
Examples from the Corpus
senile• After those first few chats with his Aunt Emily, Alec soon realised that she was slightly senile.• I know the old boy was senile.• When the mice are 10 months old they begin, reliably, to get senile.• Rumors were rampant that the octogenarian was senile and in poor health.• His lawyers claim he is senile and incompetent to stand trial.• Mr Allsopp was known to suffer from senile dementia and was often seen walking in the area.• In this sense the world would be a better place without mental retardation, madness, and senile dementia.• Certainly those working with the mentally ill or the handicapped or the senile or in health education may properly think it is.• He became remote, sulking, even senile possibly.going senile• Of course, Moses might have been going senile and got a bit mixed up.Origin senile (1600-1700) Latin senilis, from senex; → SENIOR1 