n pl [fr their being reckoned from the heliacal rising of the Dog Star (Sirius)]1 : the period between early July and early September when the hot sultry weather of summer usu occurs in the northern hemisphere2 : a period of stagnation or inactivity
The sultry period of summer in the northern hemisphere, when the Dog Star, Sirius, is hidden from view by the Sun's glow Almanac makers vary in the dating of this period, which lasts anywhere from four to six weeks ... between early July and early September Some English calendars now list it as the period from July 3 - August 11 Some say it is 20 days before and after the conjunction of Sirius and the Sun
The name given to the very hot summer weather that may persists for four to six weeks between mid-July through early September in the United States In western Europe, this period may exist from the first week in July to mid-August and is often the period of the greatest frequency of thunder Named for Sirius, the Dog Star, which lies in conjunction with the sun during this period, it was once believed to intensify the sun's heat during the summer months
A period of from four to six weeks, in the summer, variously placed by almanac makers between the early part of July and the early part of September; canicular days; so called in reference to the rising in ancient times of the Dog Star (Sirius) with the sun