flush

flush 1 A redness of the skin, typically over the cheeks or neck. A flush is usually temporary and brought on by excitement, exercise, fever, or embarrassment. Flushing is an involuntary (uncontrollable) response of the nervous system that leads to widening of the capillaries of the involved skin. Also referred to as a blush (or, may be used as a verb). Flushing may also be caused by medications or other substances that cause widening of the capillaries. 2 To wash out a wound, body area, or medical device.