What does moulted mean?
Moulted is the past tense and past participle of moult, a verb meaning to shed an old outer covering and grow a replacement. The process is especially familiar in birds, which moult worn or damaged feathers, and in insects and other arthropods, which shed an exoskeleton before growing a larger one. Snakes also moult their skin, while mammals may moult their coats. The word is more precise than the informal use of shed, because it implies a regular biological cycle of replacement rather than merely the loss of something. In everyday speech, a person may say that they have moulted or shed their hair, especially when it comes out heavily during a seasonal change. Moult is the usual British spelling; the traditional American spelling is molt. The word can also describe the complete process, as in a reference to a bird’s annual moulting season.
verbTo shed old feathers, hair, skin, or an outer covering and grow a replacement. It is the past tense and past participle of moult.
- To shed and replace old feathers, hair, skin, or another outer covering.
- To undergo this process of shedding and replacement.
"The young bird has moulted its down and developed a coat of flight feathers."
"The cat has moulted all over the sofa."
"Snakes commonly moult their skin as they grow."
A snake’s shed skin is proof of moulting: the old covering left behind while a fresh, larger one formed underneath.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does moulted come from?
Moult comes through Middle English from Old French molt, ultimately from Vulgar Latin *multare, derived from Latin mutare, meaning “to change.” The modern American spelling molt reflects a different historical treatment of the same word rather than a separate meaning. Its established relatives include the American variant molt and the derivative moulter, meaning a bird that moults or a person engaged in the practice.
Related word forms
How moulted is actually used
Moult is especially associated with birds and arthropods but is also used of mammals and snakes. In American English, molt is the usual spelling. The British verb shed is more informal and often describes a person’s hair rather than a formal process of replacement.
Easily confused with moulted
Moult is the standard British spelling, while molt is the standard American spelling of the same verb.
To moult is to shed and replace an outer covering, whereas to moulder is to decay, especially through dampness.