What do you call a teen dog?

There isn't a specific term for a teen dog, like there is for a teen human. However, you can describe a dog in its teenage years as:

* Adolescent

* Young adult

* Mature puppy

* Teenager (though this is more informal)

You can also use age-specific terms like:

* One-year-old

* Two-year-old

Ultimately, the best way to describe a teen dog is to be clear and specific about its age.