Adjacent Words

Lunacy definitions

	Tweet

Webster's 1828 Dictionary

LU'NACY, n. [from L. luna, the moon.]
1. A species of insanity of madness, supposed to be influenced by the moon, or periodical in the month.
2. Madness in general.

WordNet (r) 3.0 (2005)

n
1: obsolete terms for legal insanity [syn: lunacy, madness, insaneness]
2: foolish or senseless behavior [syn: folly, foolery, tomfoolery, craziness, lunacy, indulgence]

Merriam Webster's

noun (plural -cies) Etymology: lunatic Date: 1541 1. a. insanity b. intermittent insanity once believed to be related to phases of the moon 2. wild foolishness ; extravagant folly 3. a foolish act

Oxford Reference Dictionary

n. (pl. -ies) 1 insanity (orig. of the intermittent kind attributed to changes of the moon); the state of being a lunatic. 2 Law such mental unsoundness as interferes with civil rights or transactions. 3 great folly or eccentricity; a foolish act.

Webster's 1913 Dictionary

Lunacy Lu"na*cy, n.; pl. Lunacies. [See Lunatic.] 1. Insanity or madness; properly, the kind of insanity which is broken by intervals of reason, -- formerly supposed to be influenced by the changes of the moon; any form of unsoundness of mind, except idiocy; mental derangement or alienation. --Brande. --Burrill. Your kindred shuns your house As beaten hence by your strange lunacy. --Shak. 2. A morbid suspension of good sense or judgment, as through fanaticism. --Dr. H. More. Syn: Derangement; craziness; mania. See Insanity.

Collin's Cobuild Dictionary

1. If you describe someone's behaviour as lunacy, you mean that it seems very strange or foolish. ...the lunacy of the tax system... It remains lunacy to produce yet more coal to add to power stations' stockpiles. [disapproval] 2. Lunacy is severe mental illness. (OLD-FASHIONED)

Soule's Dictionary of English Synonyms

n. Insanity, madness, mania, derangement, craziness, mental aberration, crack.

Moby Thesaurus

aberration, abnormality, absurdity, alienation, asininity, battiness, brain damage, brainlessness, brainsickness, buffoonery, clouded mind, clownishness, crackpottedness, crankiness, craziness, daffiness, daftness, dementedness, dementia, derangement, desipience, disorientation, distraction, eccentricity, fatuity, fatuousness, folie, folly, foolery, foolhardiness, foolheadedness, foolishness, frivolity, frivolousness, furor, giddiness, goofiness, idiocy, illogic, illogicality, imbecility, inanity, ineptitude, insaneness, insanity, irrationality, loss of mind, loss of reason, madness, mania, mental deficiency, mental derangement, mental disease, mental disorder, mental disturbance, mental illness, mental instability, mental sickness, mind overthrown, mindlessness, mindsickness, niaiserie, nugacity, nuttiness, oddness, pixilation, possession, preposterousness, psychopathy, psychosis, queerness, rabidness, reasonlessness, ridiculousness, sappiness, screwiness, senselessness, shattered mind, sick mind, sickness, silliness, strangeness, stupidity, thoughtlessness, triflingness, triviality, unbalance, unbalanced mind, unsaneness, unsound mind, unsoundness, unsoundness of mind, wackiness, weirdness, witlessness, zaniness, zanyism