dog days

plural noun

Definition of dog days 

1 : the period between early July and early September when the hot sultry weather of summer usually occurs in the northern hemisphere

2 : a period of stagnation or inactivity

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Did You Know?

Dogs aren’t the only creatures uncomfortable in oppressive heat, so why does a dog get singled out in dog days? The dog here is actually the Dog Star, which is also called Sirius. The star has long been associated with sultry weather in the northern hemisphere because it rises simultaneously with the sun during the hottest days of summer. In the ancient Greek constellation system, this star (called Seirios in Greek) was considered the hound of the hunter Orion and was given the epithet Kyon, meaning "dog." The Greek writer Plutarch referred to the hot days of summer as hēmerai kynades (literally, "dog days"), and a Latin translation of this expression as dies caniculares is the source of our English phrase.

Examples of dog days in a Sentence

Recent Examples on the Web

In time for the dog days of summer, Amtrak customers traveling all around the Midwest can bring their small to medium-sized pets on board trains. Mary Wisniewski,, "Pets now allowed on all Amtrak Midwest routes," 13 July 2018 And a 55-degree ocean is pretty darn effective at easing those dog days of August. Paul Cappiello, The Courier-Journal, "There's no such thing as 'average' Kentucky weather. And trees hate that," 13 July 2018 The dog days of summer are here, which means vacations — and staycations — for many of us. Dan Wine,, "7 things to do in Orlando this summer — and they're all free," 12 July 2018 The dog days of August are typically not when voters are tuned in to midterm elections. New York Times, "Senate’s August Recess Cut, Keeping Democrats Off Campaign Trail," 5 June 2018 Polished blowouts and artful half buns may reign supreme in spring, but the dog days of summer warrant a no-fuss, stay-put style—and preferably one that can take you from beach time to happy hour. Jenna Rennert, Vogue, "Plaits, Please! The Best Memorial Day Weekend Braid Inspiration On Instagram," 26 May 2018 As the dreaded dog days of summer approach, don’t submit to the sweltering heat. Valerie Bonk, Howard County Times, "10 ways to beat the heat in Howard County this summer," 6 June 2018 Here are this week’s bite-size theater reviews as the 2017-18 theater scene starts winding up for the dog days. Kerry Lengel, azcentral, "Bite-size theater reviews: 'Flora and Ulysses,' 'Bury the Hatchet,' 'Godspell'," 4 May 2018 The dog days of summer are upon us, and there's no better way to cool off than with a sweet frozen treat. Redbook, "Frosty Friday: 4 Popsicles and Ice Cream Sandwiches to Help You Beat the Heat," 22 July 2011

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'dog days.' 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 dog days

1538, in the meaning defined at sense 1

History and Etymology for dog days

from their being reckoned from the heliacal rising of the Dog Star (Sirius)

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The first known use of dog days was in 1538

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More Definitions for dog days

dog days


English Language Learners Definition of dog days

: the hottest time of the year

dog days

noun plural

Kids Definition of dog days

: the hot period between early July and early September

More from Merriam-Webster on dog days

See words that rhyme with dog days Encyclopedia article about dog days

Comments on dog days

What made you want to look up dog days? Please tell us where you read or heard it (including the quote, if possible).


exaggeratedly or childishly emotional

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