The meaning of INSANE is exhibiting a severely disordered state of mind. How to use insane in a sentence.

INSANE definition: 1. very annoyed, angry, upset, or excited, often so that you cannot think or behave normally: 2…. Learn more.

Insane definition: (not in technical use as a medical diagnosis) not sane; not of sound mind; mentally deranged.. See examples of INSANE used in a sentence.

If you describe a decision or action as insane, you think it is very foolish or excessive.

Define insane. insane synonyms, insane pronunciation, insane translation, English dictionary definition of insane. afflicted with mental derangement, having a disordered mind, mad: Her bizarre threats …

WordReference Random House Unabridged Dictionary of American English © 2025 in•sane (in sān′), adj. not sane; not of sound mind; mentally deranged. of, pertaining to, or characteristic of a person …

insane, adj. & n. meanings, etymology, pronunciation and more in the Oxford English Dictionary