acorn

noun

ˈā-ˌkȯrn  -kərn 

: the nut of the oak usually seated in or surrounded by a hard woody cupule of indurated bracts

Illustration of acorn

Examples of acorn in a Sentence

Recent Examples on the Web

This includes leaves, acorns, seed pods, twigs, and even fallen branches, unless your neighbor was neglecting a diseased and rotting tree. —Brandee Gruener, Southern Living, 30 Sep. 2025

Williams shared the importance of every generation’s role in preserving traditional acorn gathering and cooking. —Veronica Fernandez-Alvarado, Sacbee.com, 27 Sep. 2025

Stack pumpkins of varying sizes on your steps, fill a wooden crate with gourds or scatter pinecones, acorns and wheat bundles along the porch rail. —Angie Hicks, Boston Herald, 25 Sep. 2025

Female and male participate in harvesting and storing acorns, take part in incubating eggs and feeding young. —Cecilia Rodriguez, Forbes.com, 18 Sep. 2025

Word History

Etymology

Middle English akorn, akkorn (partially assimilated to corn "kernel, corn entry 1"), hakerne, accherne, accharne, going back to Old English æcern, going back to Germanic *akrana- (whence also Middle High German ackeran "tree nuts," Old Norse akarn, Gothic akran "fruit, produce"); akin to Old Irish írne "sloe, kernel," Welsh eirin "plums, sloes," aeron "fruits, berries," going back to Celtic *agrinyo-, *agranyo-; perhaps further akin to a Balto-Slavic word with an initial long vowel (Old Church Slavic agoda "fruit," Polish jagoda "berry," Lithuanian úoga)

Note: Taken to be a derivative of Indo-European *h₂eǵros "uncultivated field, pasture" (see acre), though this would seem to exclude the Balto-Slavic etymon, which lacks the suffix, from consideration. It is also not clear if fields, uncultivated or not, are the source of wild tree nuts.

First Known Use

before the 12th century, in the meaning defined above

Phrases Containing acorn

• acorn squash
• acorn woodpecker
• acorn worm

Kids Definition

acorn

noun

ˈā-ˌkȯrn  -kərn 

: the roundish one-seeded thin-shelled nut of an oak tree usually having a woody cap