Mental illness or derangement. No longer in scientific use.
Law
Unsoundness of mind sufficient in the judgment of a civil court to render a person unfit to maintain a contractual or other legal relationship or to warrant commitment to a mental health facility.
In most criminal jurisdictions, a degree of mental malfunctioning sufficient to relieve the accused of legal responsibility for the act committed.
Extreme foolishness; folly.
Something that is extremely foolish.
Extreme foolishness; folly.
Something that is extremely foolish.
Synonyms: These nouns denote conditions of serious mental disability. Insanity is a grave, often prolonged condition that prevents a person from being held legally responsible for his or her actions: was judged not guilty for reasons of insanity. Lunacy often denotes derangement relieved intermittently by periods of clear-mindedness: yelled wildly in a moment of utter lunacy. Madness often stresses the violent aspect of mental illness: a story about obsession and madness. Mania refers principally to the excited, or manic, phase of bipolar disorder: prescribed drugs to control the patient's periods of mania. Dementia implies mental deterioration brought on by an organic brain disorder: underwent progressive stages of dementia.
Ab`er*ra"tion\, n. [L. aberratio: cf. F. aberration. See Aberrate.]1. The act of wandering; deviation, especially from truth or moral rectitude, from the natural state, or from a type. "The aberration of youth." --Hall. "Aberrations from theory." --Burke. 2. A partial alienation of reason. "Occasional aberrations of intellect." --Lingard. Whims, which at first are the aberrations of a single brain, pass with heat into epidemic form. --I. Taylor. 3. (Astron.) A small periodical change of position in the stars and other heavenly bodies, due to the combined effect of the motion of light and the motion of the observer; called annual aberration, when the observer's motion is that of the earth in its orbit, and daily or diurnal aberration, when of the earth on its axis; amounting when greatest, in the former case, to 20.4", and in the latter, to 0.3". Planetary aberration is that due to the motion of light and the motion of the planet relative to the earth. 4. (Opt.) The convergence to different foci, by a lens or mirror, of rays of light emanating from one and the same point, or the deviation of such rays from a single focus; called spherical aberration, when due to the spherical form of the lens or mirror, such form giving different foci for central and marginal rays; and chromatic aberration, when due to different refrangibilities of the colored rays of the spectrum, those of each color having a distinct focus. 5. (Physiol.) The passage of blood or other fluid into parts not appropriate for it. 6. (Law) The producing of an unintended effect by the glancing of an instrument, as when a shot intended for A glances and strikes B. Syn: Insanity; lunacy; madness; derangement; alienation; mania; dementia; hallucination; illusion; delusion. See Insanity.
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