|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|
|[C16: translation of Late Latin diēs caniculārēs, translation of Greek hēmerai kunades]|
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.
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.
periods of exceptionally hot and humid weather that often occur in July, August, and early September in the northern temperate latitudes. The name originated with the ancient Greeks, Romans, and Egyptians; they believed that Sirius, the dog star, which rises simultaneously with the Sun during this time of the year, added its heat to the Sun's and thereby caused the hot weather. Their belief that dogs were subject to spells of madness at this time also may have contributed to the name. Because people tended to become listless during the dog days, Sirius was held to have a detrimental effect on human activities
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