molt

American  

[mohlt] / moʊlt /

especially British, moult

verb (used without object)

1. (of birds, insects, reptiles, etc.) to cast or shed the feathers, skin, or the like, that will be replaced by a new growth.

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verb (used with object)

1. to cast or shed (feathers, skin, etc.) in the process of renewal.

noun

1. an act, process, or an instance of molting.

2. something that is dropped in molting.

molt British  

/ məʊlt /

verb

1. the usual US spelling of moult

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molt Scientific  

/ mōlt /

1. To shed an outer covering, such as skin or feathers, for replacement by a new growth. Many snakes, birds, and arthropods molt.

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Other Word Forms

• molter noun

Etymology

Origin of molt

1300–50; earlier mout (with intrusive -l-; cf. fault, assault), Middle English mouten, Old English -mūtian to change (in bi-mūtian to exchange for) < Latin mūtāre to change; see mutate

Explanation

When an animal molts, it loses its feathers, fur, skin or maybe even outer skeleton. People don't molt, but plenty of animals do as a normal part of their life cycle. Despite the guarantees made by late night advertisements, once a human is bald, he's bald forever. Not so for many animals who routinely lose and gain hair, skin or feathers. Think of shedding dogs and snakes crawling out of their old skins. This is the process known as molting. Insects that molt lose their shells or wings, often a sign that they're entering a different part of their life cycle.

Example Sentences

They molt multiple times, eventually becoming something less shrimpy and more lobsterlike, called a megalopa.

From Slate • Aug. 19, 2025

However, larger species such as great horned owls tend to molt slower, and can take two or more years to replace all their feathers.

From Los Angeles Times • Aug. 16, 2025

Mr. Rave says that after the eggs hatch, many of the mothers go off to molt.

From NewsForKids.net • May 7, 2024

A few days after they emerge and molt, the males will start buzzing in an effort to find a mate, a slow-building crescendo of noise that in a chorus can be louder than a plane.

From New York Times • Jan. 19, 2024

As the spiders molt and grow, the net is enlarged.

From "Silent Spring" by Rachel Carson