dog days

American  

plural noun

1. the sultry part of the summer, supposed to occur during the period that Sirius, the Dog Star, rises at the same time as the sun: now often reckoned from July 3 to August 11.

2. a period marked by lethargy, inactivity, or indolence.

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dog days British  

plural noun

1. the hot period of the summer reckoned in ancient times from the heliacal rising of Sirius (the Dog Star)

2. a period marked by inactivity

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dog days Cultural  

1. The hot, muggy days of summer. The Romans associated such weather with the influence of Sirius, the dog star, which is high in the sky during summer days.

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dog days Idioms  

1. Hot, sultry summer weather; also, a period of stagnation. For example, It's hard to get much work done during the dog days, or Every winter there's a week or two of dog days when sales drop dramatically. The term alludes to the period between early July and early September, when Sirius, the so-called Dog Star, rises and sets with the sun. The ancient Romans called this phenomenon dies caniculares, which was translated as “dog days” in the first half of the 1500s.

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Other Word Forms

• dog-day
  adjective

Etymology

Origin of dog days

1530–40; translation of Latin diēs caniculārēs; see canicular

Example Sentences

See Examples For:

dog days

During the dog days of his reign at Rangers, Russell Martin was once asked if he could name one or two things that were better on his watch - and he couldn't do it.

From BBC ● Aug. 27, 2026

In the dog days of summer, there’s no better place to escape the heat than inside the air-conditioned paradise of a movie theater.

From Salon ● Aug. 15, 2026

The only one I’m aware of is that August comes during the so-called dog days of summer, when trading volume is relatively light.

From MarketWatch ● Jul. 23, 2026

He arrived just as the dog days of summer were becoming ferocious.

From Los Angeles Times ● Sep. 23, 2025

It was warm, too, more like the dog days of summer than the breezy beginnings of it.

From "Miss Peregrine's Home for Peculiar Children" by Ransom Riggs