molt

verb \ ˈmōlt \

|Updated on: 13 Jun 2018

Definition of molt

: to shed hair, feathers, shell, horns, or an outer layer periodically

Birds molt once or twice a year.

: to cast off (an outer covering) periodically; specifically : to throw off (the old cuticle (see cuticle 1) —used of arthropods

a spider, like a lobster, molts its covering as it grows
—Eugene Kinkead

—

molter

noun

See molt defined for English-language learners

See molt defined for kids

Examples of molt in a Sentence

Snakes molt as they grow, shedding the old skin and growing a larger new skin.
a crab molts its shell as it grows larger

Recent Examples of molt from the Web

About 70% of Canada geese from Wisconsin fly to Ontario to molt, with most in the James Bay region, Finger said.

— paul a. smith, Milwaukee Journal Sentinel, "Smith: Canada geese grouping up before molt migration," 9 June 2018
See another video of the same species molting, and learn more about the spider.

— amy rankin, National Geographic, "A Tarantula Sheds Its Skin in New Time-Lapse Video," 16 May 2018
During molting season, their appetite almost doubles.

— grace wong, chicagotribune.com, "What do a sommelier, a Bears lineman and a penguin eat for lunch?," 26 Apr. 2018
Area songbirds are slowly but steadily molting into their breeding plumage.

— taylor piephoff, charlotteobserver, "Yellow-rumped warblers become brighter for breeding | Charlotte Observer," 12 Apr. 2018
Some snakes can molt to remove the fungus, others aren’t so lucky.

— avery thompson, Popular Mechanics, "A Mysterious Disease Is Killing Snakes Around the World," 23 Dec. 2017
The lesions, which spread quickly across a snake's body from the disease, may dissipate by molting.

— josh hafner, USA TODAY, "'Worst-case scenario': Deadly snake fungus threatens species across the world," 21 Dec. 2017
But molting snakes tend to bask in the sun for longer periods, an act that leaves them vulnerable to starvation and predators.

— josh hafner, USA TODAY, "'Worst-case scenario': Deadly snake fungus threatens species across the world," 21 Dec. 2017
Because birds molt their feathers each year, the amount of soot on each bird would be a snapshot of the black carbon in the atmosphere for the year it was collected.

— jason daley, Smithsonian, "Sooty Bird Feathers Reveal a Century of Coal Emission History," 10 Oct. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'molt.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of molt

alteration of Middle English mouten, from Old English -mūtian to change, from Latin mutare — more at mutable

NEW! Time Traveler

First Known Use: 15th century

in the meaning defined at intransitive sense

See Words from the same year

molt Synonyms

Synonyms

exfoliate, shed, slip, slough (also sluff);

Related Words

flake, peel, scale;

chuck, discard, ditch, fling (off or away), jettison, junk, scrap, shuck (off), throw away, throw out, unload;

Other Insect Terms

drone, entomology, gadfly, pismire, proboscis, vespine

molt

noun

Definition of molt

: the act or process of molting; specifically : ecdysis

Recent Examples of molt from the Web

Each summer the birds shed, or molt, their wing and tail feathers.

— paul a. smith, Milwaukee Journal Sentinel, "Smith: Canada geese grouping up before molt migration," 9 June 2018
In addition to hola and gràcies, bon día (good morning), si us plau (please), merci (thanks), and molt bó (very good, as in food) will be useful.

— sara mccarty, Condé Nast Traveler, "The Essential Things to Know Before You Visit Barcelona," 5 Mar. 2018
The females will not change as much during the molt.

— taylor piephoff, charlotteobserver, "American goldfinches sport a new look this time of year | Charlotte Observer," 11 Feb. 2018
In winter, tens of thousands of the threatened Steller's eider sea ducks stay in Izembek and molt.

— author: juliet eilperin, Anchorage Daily News, "Interior Department strikes deal with Alaska village for road through national wildlife refuge," 6 Jan. 2018
The eruption would have coincided with their annual molt, which leaves the penguins vulnerable and unable to enter the water.

— aaron sidder, National Geographic, "Erupting Volcano May Have Destroyed Huge Penguin Colony," 6 July 2016
After the megalopa phase, crabs molt another seven or eight times to transform into their crab shape.

— sara sneath, NOLA.com, "Does coastal erosion help or harm the Gulf's blue crabs?," 20 Oct. 2017
That molt essentially wiped out the soot that had accumulated in their plumage.

— ben guarino, Washington Post, "Soot caught in bird feathers shows how catastrophic air pollution can be," 9 Oct. 2017
There’s the annual molt, during which even the crows are disheveled and pencil-necked.

— murr brewster, The Christian Science Monitor, "Why every writer needs a tree," 13 Sep. 2017

Origin and Etymology of molt

see ¹molt

NEW! Time Traveler

First Known Use: 1815

in the meaning defined above

See Words from the same year

Other Insect Terms

drone, entomology, gadfly, pismire, proboscis, vespine

MOLT Defined for English Language Learners

molt

verb

Definition of molt for English Language Learners

biology : to lose a covering of hair, feathers, etc., and replace it with new growth in the same place

MOLT Defined for Kids

molt

verb \ ˈmōlt \

Definition of molt for Students

molted; molting

: to shed outer material (as hair, shell, or horns) that will be replaced by a new growth

Medical Dictionary

molt

intransitive verb \ ˈmōlt \

variants: or chiefly British moult

medical Definition of molt

: to shed hair, feathers, shell, horns, or an outer layer periodically

transitive verb

: to cast off (an outer covering) periodically; specifically : to throw off (the old cuticle) —used of arthropods

molt

noun

variants: or chiefly British moult

medical Definition of molt

: the act or process of molting; specifically : ecdysis

Learn More about molt

See words that rhyme with molt Thesaurus: All synonyms and antonyms for molt Spanish Central: Translation of molt Nglish: Translation of molt for Spanish speakers Britannica English: Translation of molt for Arabic speakers Britannica.com: Encyclopedia article about molt

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molt

Definition of molt

molter

Examples of molt in a Sentence

Recent Examples of molt from the Web

Origin and Etymology of molt

molt Synonyms

Synonyms

Related Words

Other Insect Terms

molt

Definition of molt

Recent Examples of molt from the Web

Origin and Etymology of molt

Other Insect Terms

MOLT Defined for English Language Learners

molt

Definition of molt for English Language Learners

MOLT Defined for Kids

molt

Definition of molt for Students

Medical Dictionary

molt

medical Definition of molt

molt

medical Definition of molt

Learn More about molt

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