Definition & Meaning of "lens hood"

What is a "lens hood"?

A lens hood is an accessory attached to the front of a camera lens to block stray light from entering the lens and causing unwanted glare or lens flares. It helps improve image contrast and color saturation by preventing light from hitting the lens at angles that could reduce the quality of the photograph. Additionally, a lens hood provides some protection for the lens from accidental bumps and scratches.