おなonaiどしdoshi
1.

A term used to describe individuals who were born in the same year, indicating that they share the same age.

2.

A phrase that signifies a shared age among people, often used in contexts like social relationships or familial connections.

3.

A term referring specifically to people who are of identical age, highlighting a commonality in life experiences related to age.

Example:

君と僕とは同い年だ。