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lunacy

lunacy

22 7.5
Extremely foolish behavior that shows very poor judgment
  • noun
  • /ˈluːnəsi/
translation icon : locura
  • His decision to invest all his savings in a failing company was sheer lunacy.
  • sheer lunacy
  • complete lunacy
  • pure lunacy

The ideology they subscribe to is utter lunacy.

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Examples

  • Why, this is lunacy!

  • But I could think of no scam that wasn't sheer lunacy.

    Fiction book (1992)
  • It's an act of lunacy, General, sir.

  • And what fresh lunacy is this?

  • We need to keep the pressure on all the time until this lunacy stops.

    Blog text (2)
  • First Tom and now Robert: this lunacy seemed to be a disease sweeping London like the plague.

    Fiction book (1993)
  • Day after day, from the radio and the newspapers, all we heard from Europe was the lunacy of approaching war.

    Fiction book (1997)
  • Yes, well, under the circumstances it seems a little churlish not to meet the woman responsible - for this voyage of lunacy.

  • Hundreds of conspiracy-oriented internet sites, of various degrees of lunacy, appeared almost overnight.

    Fiction book (2002)
  • However, fewer and fewer Americans are embracing the lunacy of trying to force religious beliefs on anyone else.

    Blog text (8)

Synonyms

insanity
vslunacy
231 6.5

A serious mental illness that makes a person unable to think or behave normally

emphasizes extreme foolish conduct rather than clinical illness
madness
vslunacy
112 4.6

A foolish action that shows poor judgment

is stronger, meaning extreme or extreme-seeming foolish behaviour
craziness
vslunacy
68 4.2

Very wild or foolish behavior, sometimes caused by problems in the mind

leans more toward extreme folly rather than general instability
folly
vslunacy
59 7.3

A foolish action or a lack of good sense that causes trouble

is used for very extreme or strikingly senseless conduct
absurdity
vslunacy
54 6.1

Something very silly that goes against common sense

focuses more on extreme foolishness rather than mere illogic
idiocy
vslunacy
  • Offensive
40 8.0

Very stupid or foolish behaviour often seen as offensive

adds a sense of wild or extreme folly beyond mere stupidity
irrationality
vslunacy
12 6.2

A lack of clear, logical thinking

adds intensity, meaning very extreme or senseless behaviour
ridiculousness
vslunacy
10 4.9

Being very silly or clearly unreasonable

is about deep, extreme folly rather than just being laughable
batshit
vslunacy
  • Offensive
4 9.9

An informal word for very crazy behavior or wild actions

means severe foolishness but without the slangy exaggeration
foolery
vslunacy
2 6.1

Silly, harmless behavior that makes people laugh

is more intense, implying extreme or dangerous folly
mishegoss
vslunacy
  • Slang
1 9.9

Silly, often annoying behavior that causes confusion

is harsher, implying truly extreme or serious folly
nuttery
vslunacy
  • Slang
1 9.4

Wild, foolish behavior that causes confusion

is similar but is less tied to casual or joking tone
looniness
vslunacy
  • Informal
1 6.8

A very silly or crazy way of behaving that makes people laugh

is more about extreme or alarming foolishness rather than silliness
daftness
vslunacy
  • Informal
1 7.3

A way of behaving that is silly or foolish and not thinking clearly

means a stronger, more serious kind of foolish behaviour
preposterousness
vslunacy
1 7.9

A state of being very silly and clearly against common sense

is more about severe, maddening foolish behaviour than absurdity
insaneness
vslunacy
  • Archaic
9.9

A condition that makes a person very ill in the mind

is the modern sense focused on extreme foolish behaviour
absurdness
vslunacy
7.3

A situation that is very strange and does not make sense

stresses extreme folly and near madness rather than only illogic

Antonyms

3.7

Good practical judgment about what to do

571 2.7

To use what you know and have learned to make good choices and give good advice

How Foolish

lunacy
22 7.5
foolishness
61 2.7
silliness
29 2.6

Surface Forms

lunacy singular
lunacies plural

Morphology

lunacy = lunatic (transparent) = lunatic + y

The sense 'foolish or senseless behavior' is a direct nominalization of 'lunatic' (extreme madness or folly), so the relation is clear.

Etymology

The word lunacy comes from the Latin word luna 'moon', and a helpful way to remember it is to think of the moon making people act strange. So today lunacy often means very foolish or wildly risky behavior.