— dog-day , adj.
1. the sultry part of the summer, supposed to occur during the period that Sirius, the Dog Star, rises at the same time as the sun: now often reckoned from July 3 to August 11.
2. a period marked by lethargy, inactivity, or indolence.
[ 1530-40; trans. of L dies caniculares; see CANICULAR ]