moult UK /mɒlt/US /moʊlt/noun 2verb 2forms 3 noun2 •The process of shedding or losing a covering of fur, feathers or skin etc.Some birds change colour during their winter moult. •The skin or feathers cast off during the process of moulting. verb2 •To undergo the process of shedding or losing a covering of hair or fur, feathers, skin, horns, etc, and replacing it with a fresh one; to change by moulting.Birds moult periodically. •To shed in such a manner.Turtle-droves […] moulted their feathers. — 1929 formsmoulted · moulting · moults