Solid white (chicken plumage)
In poultry standards, solid white is coloration of plumage in chickens (Gallus gallus domesticus) characterized by a uniform pure white color across all feathers, which is not generally associated with depigmentation in any other part of the body. Color is an important feature of most living organisms.
Source: Wikipedia — Solid white (chicken plumage) (CC BY-SA 4.0)