The noun insanity can be countable or uncountable. In more general, commonly used, contexts, the plural form will also be insanity. However, in more specific contexts, the plural form can also be insanities e.g. in reference to various types of insanities or a collection of insanities.
Is insanity a noun or verb?
noun, plural in·san·i·ties. (not in technical use as a medical diagnosis) the condition of being insane; a derangement of the mind. Law.
How do you use insanity in a sentence?
relatively permanent disorder of the mind.
- In his defense he alleged temporary insanity.
- Insanity is doing the same thing over and over again and expecting different results.
- In her defense Halen alleged temporary insanity.
- This kind of risk borders on insanity.
- The insanity which ran in his family haunted him.
