dog day


Definition of dog day 

1a dog days plural : the period between early July and early September when the hot sultry weather of summer usually occurs

b : a day in dog days : a hot sultry day

2 dog days plural : a period marked by dull lack of progress the dog days following any major upheaval

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First Known Use of dog day

1538, in the meaning defined at sense 1a

History and Etymology for dog day

back-formation from dog days, translation of Late Latin dies caniculares, translation of Greek hēmerai kynades; from their being reckoned in ancient times from the heliacal rising of the Dog Star (Sirius)

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The first known use of dog day was in 1538

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playful or foolish behavior

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