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dog days

noun plural

Simple Definition of dog days

  • : the hottest time of the year

Full Definition of dog days

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

  2. 2 :  a period of stagnation or inactivity

Origin of dog days

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

First Known Use: 1538

Other Climate/Meteorology Terms

DOG DAYS Defined for Kids

dog days

noun plural

Definition of dog days

  1. :  the hot period between early July and early September

History for dog days

The brightest star in the sky is Sirius, also known as the Dog Star. Sirius was given this name by the ancients because it was considered the hound of the hunter Orion, whose constellation was nearby. The Dog Star was regarded by the ancient Greeks as the bringer of scorching heat, because its early-morning rising coincided with the hottest summer days of July and August. The Greek writer Plutarch called this time hēmerai kynades, literally, “dog days”—the days of the Dog Star—and by way of Latin this phrase was translated into English as dog days.

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February 7, 2016

a slight offense

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