dog days

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.

dog days

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

dog days

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.

Other Word Forms

• dog-day adjective

Word History and Origins

Origin of dog days¹

1530–40; translation of Latin diēs caniculārēs; canicular

Word History and Origins

Origin of dog days¹

C16: translation of Late Latin diēs caniculārēs, translation of Greek hēmerai kunades

Idioms and Phrases

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.