The term 'DOG'S AGE' can be solved by two crossword solutions: EON (3 letters) and LONGTIME (8 letters). An EON is an indefinite and very long period of time, typically one billion years. It is often used to describe a very long period of time in the past or future. A LONGTIME is a period of time that has been going on for a long time. It is usually used to describe something that has been happening for a long time, such as a relationship or a job. Therefore, the two crossword solutions for the term 'DOG'S AGE' refer to a very long period of time, either in the past or present.