pouter

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun One that pouts.
• noun Any of several breeds of domestic pigeon capable of distending the crop until the breast becomes puffed out.

from The Century Dictionary.

• noun One who or that which pouts. Specifically
• noun A long-legged breed of domestic pigeons, named from their characteristic habit of pouting, or puffing up the breast, sometimes to surprising size and almost globular shape.
• noun Same as pout .
• noun A sportsman whose game is poults or young grouse.

from the GNU version of the Collaborative International Dictionary of English.

• noun One who, or that which, pouts.
• noun (Zoöl.) A variety of the domestic pigeon remarkable for the extent to which it is able to dilate its throat and breast.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A person who habitually pouts; a sourpuss
• noun A breed of pigeon that inflates its crop

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun someone with a habitually sullen or gloomy expression
• noun one of a breed of pigeon that enlarge their crop until their breast is puffed out