Syncope, or loss of consciousness owing to a sudden arrest of the blood supply to the brain, the face becoming pallid, the respiration feeble, and the heat's beat weak.

Fainting or syncope (IPA: or ) is a sudden (and generally momentary) loss of consciousness, or blacking out, owing to a lack of sufficient blood and oxygen reaching the brain. The first symptoms a person feels before fainting are dizziness, a dimming of vision, or brown-out, tinnitus, and feeling hot. Moments later, the person's vision turns black and he or she drops to the floor (or slumps if seated in a chair).