oat

American  

[oht] / oʊt /

noun

oats plural

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.

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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

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Other Word Forms

Derived Forms

• oatlike
  adjective

Inflected Forms

Nouns

• oats
  plural

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."

Example Sentences

As someone who’s vehemently lactose intolerant, I was pleased — no, elated — to see that Luckin offers not one, but three different options for non-dairy milk: Coconut, Oat and Almond.

From Salon • Jul. 27, 2025

Officials said the circular quarantine zone is roughly bordered to the north by Castaic Junction, the south by Oat Mountain, west by Del Valle Road and east by Honby Avenue.

From Los Angeles Times • Jul. 28, 2023

Oat biscuits are best for dunking in your breakfast brew, a study has revealed.

From BBC • Dec. 20, 2022

Oat milk in particular has been winning consumers — and famous investors like Oprah Winfrey — with the message that it’s healthier and more environmentally sustainable than cow’s milk.

From Seattle Times • Mar. 9, 2022

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