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.
Hsu crafts her treatments using homemade shower oil with jojoba oil which is packed with antibacterial and antioxidant properties plus vitamin E for skin repair and oat, which delivers gentle exfoliation while soothing irritation. Pooja Shah, Forbes.com, 26 Aug. 2025 Whole or halved walnuts are easy to sprinkle on top of oats and salads, or as a nutritious boost for baked treats like brownies. Abby Norman, Verywell Health, 26 Aug. 2025 Users have posted savory oat bowls made with bone broth, garlic, bok choy, tomatoes, sunny-side-up eggs and salsa. Deirdre Bardolf, FOXNews.com, 23 Aug. 2025 It is made by blending oats with water and other ingredients to create a mildly sweet and creamy drink. Jillian Kubala, Health, 19 Aug. 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 6 Sep. 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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