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oat

American  
[oht] / oʊt /

noun

  1. a cereal grass, Avena sativa, cultivated for its edible seed.

  2. (used with a singular or plural verb) Usually oats. the seed of this plant, used as a food for humans and animals.

  3. any of several plants of the same genus, as the wild oat.

  4. Archaic. a musical pipe made of an oat straw.


idioms

  1. sow one's wild oats. wild oat.

  2. feel one's oats,

    1. to feel frisky or lively.

    2. to be aware of and use one's importance or power.

oat British  
/ əʊt /

noun

  1. an erect annual grass, Avena sativa, grown in temperate regions for its edible seed

  2. (usually plural) the seeds or fruits of this grass

  3. any of various other grasses of the genus Avena, such as the wild oat

  4. poetic a flute made from an oat straw

  5. informal

    1. to feel exuberant

    2. to feel self-important

  6. slang to have sexual intercourse

  7. to indulge in adventure or promiscuity during youth

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Etymology

Origin of oat

before 900; Middle English ote, Old English āte

Explanation

An oat is a cereal grain, the seed of a plant that grows like a tall grass in fields. Your dad might love to bake with oats. You're most likely to see the noun oat in its plural form — oats. Oats are grown for both animal feed and human consumption. If you ever eat oatmeal for breakfast, you know what an oat looks like, at least in its rolled, flake-like form. The Old English root is ate, "grain of the wild oat plant." The source of this word isn't known for sure, though it may come from the Old Norse eitill, "nodule" or "single grain."

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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.

By most accounts, packages arrived on schedule, while consumers jonesing for Iced Brown Sugar Oat Milk Shaken Espressos almost certainly managed to find sugar and succor elsewhere.

From Los Angeles Times • Jan. 3, 2025

It sold an oat-based chocolate bar called Oat Made in some test markets starting in 2021.

From Seattle Times • Mar. 7, 2023

Chocolate Cheerios has 11 grams, Honey Nut has 12, Oat Crunch has 15, and so on.

From Washington Post • Feb. 24, 2022

Oat flour is maybe the only gluten-free alternative that is flax egg-friendly.

From Salon • Oct. 17, 2021

But you have to remember that people can't be good at cricket unless they teach themselves to be so, and Oat jousting was an art, just as cricket is.

From "The Once and Future King" by T. H. White