Suffering from dementia or a loss of cognitive function.(adjective)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "demented" in a sentence
"The word 'demented' like 'nutter' or 'lunatic' is a real barrier to sufferers, such as myself, in discussing mental illness, and so overcoming the terrible awkwardness that makes us feel like social lepers."
"Your use of the word 'demented' is not totally surprising, given how pervasive and entrenched the mythology about the poet is out there (and how easy it has been for centuries to automatically label gifted, creative women who behave differently as 'demented')."
"Too bad dr demented is too dense to understand what you are trying to say to them .."