dog's age

American  

noun

Northern U.S.

1. quite a long time.

   I haven't seen you in a dog's age!

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dog's age Idioms  

1. see under coon's age.

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Etymology

Origin of dog's age

An Americanism dating back to 1830–40

Example Sentences

They are also digging into whether AI could correctly identify a dog's age, gender and breed based on what it woofs.

From BBC

Bobi's owner, Leonel Costa, has not commented on the record's removal, but had previously said suspicions over the veracity of the dog's age were "unfounded".

From BBC

The group said it had received correspondence from some vets questioning the dog’s age and took note of public commentary from vets and other professionals.

From Seattle Times

Here’s the conversion formula the scientists came up with: Human age is equal to 16 multiplied by the natural logarithm of the dog’s age, plus 31.

From Seattle Times

Before that teaser, Ms. Grande’s last Instagram post on the line was weeks ago, and the one before that, a tutorial on how to achieve her “signature” makeup look, was in early February, which is a dog’s age in social media marketing.

From New York Times