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

Per InStyle, the earrings were a gift from her mother, Carole Middleton, and designed to resemble the Middleton coat of arms, with oak leaves and acorns. —Kathleen Walsh, Glamour, 21 May 2025

Each has a tag that lists its origin: acorns collected in Bergen County, New Jersey, or in the Bronx or Westchester, then sprouted at a Forest Service facility and transported here. —Robert Sullivan, Curbed, 9 June 2025

Why Are Deer Damaging My Garden? Deer will eat whatever’s seasonally abundant and available, so their diets change throughout the year to include things such as fruit, vegetables, mushrooms, grass, acorns, and crops. —Arricca Elin Sansone, Southern Living, 7 June 2025

The bears have a habit of coming into Heathrow in the fall when the acorns fall and then leave. —Letters To The Editor, The Orlando Sentinel, 18 May 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