dogs age

dog's age or coon's age  {n.},  {informal}
A very long time. Usually used after "for" or "in" with a negative.
Charlie Brown! I haven't seen you for a coon's age.
Father hasn't had a night out with the boys in a dog's age.
I waited for him for a dog's age, but he didn't come.
Categories: time {informal} {n.}