Definitions for dementeddɪˈmɛn tɪd
Random House Webster's College Dictionary
crazy; insane; mad.
affected with dementia.
Origin of demented:
brainsick, crazy, demented, disturbed, mad, sick, unbalanced, unhinged(adj)
affected with madness or insanity
"a man who had gone mad"
Insane or mentally ill.
Suffering from dementia.
insane; mad; of unsound mind
The New Hacker's Dictionary
Yet another term of disgust used to describe a malfunctioning program. The connotation in this case is that the program works as designed, but the design is bad. Said, for example, of a program that generates large numbers of meaningless error messages, implying that it is on the brink of imminent collapse. Compare wonky, brain-damaged, bozotic.