We found 5 dictionaries that define the word dog's age:

General (4 matching dictionaries)

1. dog's age: Merriam-Webster
2. dog's age: Wiktionary
3. dog's age: Infoplease Dictionary
4. dog's age, dogs age: Dictionary.com

Slang (1 matching dictionary)

5. dog's age: Urban Dictionary

Definitions from Wiktionary (dog's age) ▸ noun:  (US, colloquial) A long time; many years. ▸ Words similar to dog's age ▸ Usage examples for dog's age ▸ Idioms related to dog's age ▸ Wikipedia articles (New!) ▸ Words that often appear near dog's age ▸ Rhymes of dog's age ▸ Invented words related to dog's age