Very annoyed, angry, upset, or excited, often so that you cannot think or behave normally: Learn more. Define insane.

Afflicted with mental derangement, having a disordered mind, mad: Her bizarre threats … The meaning of insane is exhibiting a severely disordered state of mind. How to use insane in a sentence. (not in technical use as a medical diagnosis) not sane; Not of sound mind; Mentally deranged.

(not in technical use as a medical diagnosis) not sane; Not of sound mind; Mentally deranged. See examples of insane used in a sentence. Wordreference random house unabridged dictionary of american english © 2025 in•sane (in sän′), adj. Not of sound mind; Mentally deranged. Of, pertaining to, or characteristic of a person … If you describe a decision or action as insane, you think it is very foolish or excessive. It denotes a state of mind that is far removed from normality, characterized by a lack of reason, coherence, or control. When applied to a person, it suggests a severe disturbance in their thoughts, …

Not of sound mind; Mentally deranged. Of, pertaining to, or characteristic of a person … If you describe a decision or action as insane, you think it is very foolish or excessive. It denotes a state of mind that is far removed from normality, characterized by a lack of reason, coherence, or control. When applied to a person, it suggests a severe disturbance in their thoughts, …

It denotes a state of mind that is far removed from normality, characterized by a lack of reason, coherence, or control. When applied to a person, it suggests a severe disturbance in their thoughts, …