noun
insanity
ihn-SA-nih-tee
noun
1
Serious mental illness; the state of being of unsound mind.
"His lawyer argued a defense of insanity."
2
Extreme foolishness or a chaotic, reckless situation.
"Trying to finish the project in one night is pure insanity."
How to Use Insanity
Learner’s notesIn plain EnglishMental illness, or (informally) sheer madness/craziness in a situation.
Common pairings
plea of insanity
sheer insanity
Word Forms
insanities plural
Study it as flashcards or scroll it in Flow — saved to your collection.
Test yourself on “insanity”
A quick quiz — meaning, synonyms & usage
→
Fill the Gap
Can you complete this real example?
His lawyer argued a defense of _____.
Etymology
From Latin insanitas, built the same way as insane — in- ("not") plus sanus ("sound, healthy").