often attributive
1
a
: any of several grasses (genus Avena)
especially : a widely cultivated cereal grass (A. sativa)
b
: a crop or plot of the oat
also : the seed of an oat
usually used in plural but singular or plural in construction
2
archaic : a reed instrument made of an oat straw

Illustration of oat

Illustration of oat
  • oat 1a
Phrases
feel one's oats
: to act in a newly self-confident and often self-important manner

Examples of oat in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Loaded with oat and wheat for a fluffy body that’s soft, smooth and perfectly balanced. Jess Fleming, Twin Cities, 18 July 2025 Stir together boiling water and rolled oats in a small heatproof bowl; let stand until room temperature, about 30 minutes, stirring occasionally to soften oats. Sheri Castle, Southern Living, 18 July 2025 Post Consumer Brands initially issued the recall on May 28 The cereal was has been pulled from stores in California and Colorado A popular oat cereal has been recalled in two states after being issued for potential metal contamination, according to the Food and Drug Administration (FDA). Escher Walcott, People.com, 17 June 2025 An easy way to start consuming them is sprinkling them into yogurt, mixing them into smoothies, or adding them to porridge or overnight oats. Morgan Fargo, Vogue, 9 July 2025 See All Example Sentences for oat

Word History

Etymology

Middle English ote "the grain of the oat plant, the plant itself," going back to Old English āte (weak feminine noun), of uncertain origin

Note: Old English āte has been compared with regional Dutch aate, oote "wild oats" (West and Zeeland Flanders), West Frisian and Groningen Dutch oat. (These contrast with Dutch haver, denoting cultivated oats, a reflex of the Common Germanic word for the grain.) Michiel de Vaan, in an addenda to the online etymologiebank.nl, believes that the Flanders words are semantic extensions of regional aat "food," of general Germanic origin (see eat entry 2), though this hypothesis would scarcely explain the Old English word. Jan de Vries (Nederlands Etymologisch Woordenboek, Brill, 1971) hypothesizes that the Low Country words may have been borrowed from English.

First Known Use

before the 12th century, in the meaning defined at sense 1a

Time Traveler
The first known use of oat was before the 12th century

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Cite this Entry

“Oat.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/oat. Accessed 29 Jul. 2025.

Kids Definition

oat

noun
: a grain that is widely grown for its long loose clusters of seeds which are used for human food and for livestock feed
oaten
ˈōt-ᵊn
adjective

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