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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