See dog days in American Heritage Dictionary 4
Origin: Translation of Late Latin diēs canīculārēs, Dog Star days (so called because the Dog Star (Sirius) rises and sets with the sun during this time)
Origin: : Latin diēs
Origin: , pl. of diēs, day
Origin: + Late Latin canīculārēs
Origin: , pl. of canīculāris, of the Dog Star.
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