noun, often attributive
\ ˈōt How to pronounce oat (audio) \

Definition of oat

1a : 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 pl. but singular or plural in construction
2 archaic : a reed instrument made of an oat straw
feel one's oats
: to act in a newly self-confident and often self-important manner

Illustration of oat

Illustration of oat

oat 1a

Examples of oat in a Sentence

Recent Examples on the Web

Instead of oats, this grain-free granola recipe uses a mix of unsweetened coconut flakes and raw nuts. Andy Baraghani, Bon Appetit, "This Tahini Granola Is Nutty, Cluster-y, and Totally Grain-Free," 9 Apr. 2018 Besides pumpkin puree, these homemade dog treats also pack additional gut-friendly fiber from oats and a dose of protein and drool-worthy flavor from peanut butter. Stephanie Eckelkamp, Good Housekeeping, "These DIY Pumpkin Oatmeal Dog Treats Are So Good You Might Just Eat Them Yourself," 3 Sep. 2018 In a large bowl, whisk together milk, eggs, and Worcestershire; stir in oats, then cumin, thyme, cayenne, 3/4 teaspoon salt, and 1/4 teaspoon pepper; let stand 5 minutes. Woman's Day Kitchen, Woman's Day, "Spicy Ketchup-Glazed Meatloaf," 18 Apr. 2018 Scott makes them with cow’s milk—or oat milk, almond milk, soy milk or water. Rachel Bachman, WSJ, "U.S. Women’s Soccer Wraps Camp, Faces France," 18 Jan. 2019 The dairy industry has complained for almost 20 years that the FDA hasn’t policed this definition as products made from soy, almonds, cashews, rice, hemp, and oats have filled shelves in the dairy aisle. Umair Irfan, Vox, "“Fake milk”: why the dairy industry is boiling over plant-based milks," 31 Aug. 2018 Based on my love of green juices, the serum contains chlorophyll and galactoarabinan, which are plant polysaccharides, and oat-grass juice. Tanisha Pina, Allure, "Dermstore’s Massive Labor Day Beauty Sale Has Already Started — Here’s What to Shop," 28 Aug. 2018 To some dairy-loving purists, the mere idea of oat milk might be the ultimate affront. Charles Passy, WSJ, "Oat Milk Causes a Stir Among Coffee Drinkers," 19 Dec. 2018 Add the coconut milk powder, coffee, baking soda, and oat flour, and blend on level 1 for one minute until a thick batter is formed. Vitamix, Bon Appetit, "Granola Crumb Cookies," 11 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'oat.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of oat

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

History and Etymology for oat

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 on-line 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.

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oat cell


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Last Updated

17 Mar 2019

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Time Traveler for oat

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

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More Definitions for oat



English Language Learners Definition of oat

: a kind of grain that is widely grown
: the seeds of the oat plant used as feed for farm animals and in foods (such as bread and oatmeal) for people


\ ˈōt How to pronounce oat (audio) \

Kids Definition of oat

1 : a cereal grass grown for its loose clusters of seeds that are used for human food and animal feed
2 oats plural : a crop or the seeds of the oat

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More from Merriam-Webster on oat

Rhyming Dictionary: Words that rhyme with oat

Spanish Central: Translation of oat

Nglish: Translation of oat for Spanish Speakers

Britannica English: Translation of oat for Arabic Speakers

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