insane

adjectives

afflicted with or characteristic of mental derangement

"was declared insane"; "insane laughter"

insane

is derived from

insaneness

is derived from

insanity

antonym

sane

is similar to

frenzied as if possessed by a demon

"the soldier was completely amuck"; "berserk with grief"; "a berserk worker smashing windows"

amok, amuck, berserk, demoniac, demoniacal, possessed

is similar to

informal or slang terms for mentally irregular

"it used to drive my husband balmy"

around the bend, balmy, barmy, bats, batty, bonkers, buggy, cracked, crackers, daft, dotty, fruity, haywire, kookie, kooky, loco, loony, loopy, nuts, nutty, round the bend, wacky, whacky

is similar to

affected with madness or insanity

"a man who had gone mad"

brainsick, crazy, demented, disturbed, mad, sick, unbalanced, unhinged

is similar to

fit to be certified as insane (and treated accordingly)

certifiable, certified

is similar to

insanely irresponsible

"an idiotic idea"

crackbrained, idiotic

is similar to

driven insane

crazed, deranged, half-crazed

is similar to

slightly insane

fey, touched

is similar to

suffering from a form of schizophrenia characterized by foolish mannerisms and senseless laughter along with delusions and regressive behavior

hebephrenic

is similar to

insane and believed to be affected by the phases of the moon

lunatic, moonstruck

is similar to

wildly disordered

"a maniacal frenzy"

maniac, maniacal

is similar to

suffering from a disorder characterized by alternating mania and depression

manic-depressive

is similar to

resembling the mania of manic-depressive illness

maniclike

is similar to

suffering from severe mental illness

"of unsound mind"

mentally ill, unsound, unstable

is similar to

not of sound mind, memory, or understanding; in law, not competent to go to trial

non compos mentis, of unsound mind

is similar to

suffering from paranoia

paranoid

is similar to

suffering from an undiagnosed mental disorder

psychopathic, psychopathologic, psychopathological

is similar to

characteristic of or suffering from psychosis

psychotic

is similar to

talking or behaving irrationally

"a raving lunatic"

raving mad, wild

is similar to

suffering from some form of schizophrenia

"schizophrenic patients"

schizophrenic

is similar to

not behaving normally

screw-loose, screwy