dog's age. A comparatively long time, though long compared to what is less clear.
Dogs who live into their teens are considered old dogs; almost none make it to 20 years. So perhaps a “dog's age” is a length of time of less than 20 years. Or it may simply be an interval of time between events that is longer than the expected interval.
A quick search of the New York Times comes up with only two metaphorical uses in the last 15 years. In both cases, the general time range referred to was a matter of years rather than decades or centuries. In the first, a discussion of crime novels in the Book Review, Marilyn Stasio complained that “Peter Lovesey hasn't written a Sergeant Cribb mystery in a dog's age;” actually it had been about fifteen years. Given that Lovesey had been cranking out Peter Diamond novels in that period of time, it surely was not a matter of his productivity or established expectation. This case might argue for the age of a dog as the frame of reference.
The second quoted hockey player Adam Graves of the New York Rangers as saying that the visiting Penguins had not lost in Madison Square Garden “in a dog's age.” I doubt that the Penguins' winning streak was more than a year or two old. In contrast, a year or two is not especially old for a dog, it is however, a relatively long time for a team to go undefeated on someone else's playing field.
1. Whitney, William Dwight and Benjamin E. Smith. 1914. The Century Dictionary and Cyclopedia; with a New Atlas of the World. New York: Century Co. Accessed from http:// www.global-language.com/century/.
2. Stasio, Marilyn. “Crime.” New York Times Book Review, Oct. 24 1993, 34.
3. Stasio, Marilyn. 1993. Crime. New York Times Book Review, Oct. 24, 34. Accessed May 23 2008 from http:// query.nytimes.com/ gst/fullpage.html? res= 9F0CE7DE1039 F937A15753C1 A965958260.