Chicken Little definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
Informal a person who spreads baseless or exaggerated reports of danger; alarmist
Origin: after the chicken in a children's story who, after being struck by a falling object, warns that the sky is falling
Chicken Little definition by American Heritage Dictionary
A confirmed pessimist, particularly one who warns of impending disaster.
Origin: After a character in a story who is hit on the head by an acorn and believes the sky is falling.