dog days, the—(also: dog days of summer, the) the hot, sultry period of summer (between early July and early September):
- During the dog days, air-conditioners are running full-time.
Note: The expression does not correlate in meaning with the phrase dog’s life—a wretched unpleasant existence:
- I never knew a sailor yet who wouldn’t tell you sailoring was a dog’s life.
three dog nights—(sl.) very cold nights:
- We had a lot of three dog nights this winter before they got the heat going to the second floor.