acorn
Americannoun
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the typically ovoid fruit or nut of an oak, enclosed at the base by a cupule.
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a finial or knop, as on a piece of furniture, in the form of an acorn.
noun
Other Word Forms
Etymology
Origin of acorn
before 1000; Middle English acorne (influenced by corn 1 ), replacing akern, Old English æcern, æcren mast, oak-mast; cognate with Old Norse akarn fruit of wild trees, Middle High German ackeran acorn, Gothic akran fruit, yield < Germanic *akrana-; alleged derivation from base of acre is dubious if original reference was to wild trees
Explanation
The nut, or fruit, that grows on oak trees is called an acorn. Chicken Little thought the sky was falling when an acorn fell on his head. Don't make that same mistake. Acorns are a distinctive nut that's often found on forest floors where oak trees grow. They are smooth and greenish, set in a rough brown base that's shaped like a little cup. The acorn is a seed, able to sprout roots if it falls in the right place, eventually growing into a new oak tree. Many animals eat acorns, some stockpiling the nuts for weeks. In Old English, æcern means "nut," from a Germanic origin.
Vocabulary lists containing acorn
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
According to scientists, the crisis is being driven by a fast-growing bear population, combined with a falling human population and poor acorn harvest pushing bears to seek food elsewhere.
From Barron's • Dec. 24, 2025
Nearby in the Rosemont Pavilion, the “Go Bowling” float loomed along with 16 other fantastical creations: chipmunks sharing an acorn, the Little Tramp dancing with his girl, B.B.
From Los Angeles Times • Dec. 31, 2024
This is before we watch her make the cheese, bake the bread and whip up the butter from fresh cream, along with preparing an acorn squash and sweet potato soup and roasting some fish.
From Salon • Jul. 31, 2024
Kim Dong-rae says this will be the final year she makes her acorn jelly.
From BBC • Mar. 12, 2024
He lifts his acorn cup, as if in salute.
From "The Cruel Prince" by Holly Black
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.