Definition of: mad

(mad) adjective mad·der, mad·dest
1. Mentally deranged; insane.
2. Subject to an overpowering emotion; excited intensely or beyond self–control: mad with jealousy or grief.
3. Colloq. Angry; furious; enraged.
4. Rabid; having hydrophobia; hence, uncontrollable.
5. Proceeding from or indicating a disordered mind; rash: a mad project.
6. Tumultuous or uncontrollable in movement or action: said of things: a mad torrent.
7. Reckless; heedless.
—noun Slang Anger; a fit of temper.
—to have a mad on Slang To be angry. [Aphetic var. of OE gemæd, gemæded, pp. of gemædan make mad <gemād insane]
—mad′ly adverb
—mad′·ness noun