Longman Dictionary of Contemporary English homepage

insanity

noun
     
in‧san‧i‧ty [uncountable]
1SCLMI the state of being seriously mentally ill, so that you cannot live normally in society [= madness]:
The court acquitted Campbell on the grounds of temporary insanity.
2 very stupid actions that may cause you serious harm [= lunacy]:
Can't they see the insanity of dumping radioactive waste in the sea?

Dictionary pictures of the day
Do you know what each of these is called?
What is the word for picture 1? What is the word for picture 2? What is the word for picture 3? What is the word for picture 4?
Click on any of the pictures above to find out what it is called.

Explore our topic dictionary