Read the dictionary definition of year. All definitions for this word.
1. a body of students who graduate together
1. the class of '97
2. she was in my year at Hoehandle High
2. the period of time that it takes for a planet (as, e.g., Earth or Mars) to make a complete revolution around the sun
1. a Martian year takes 687 of our days
3. a period of time containing 365 (or 366) days
1. she is 4 years old
2. in the year 1920
4. a period of time occupying a regular part of a calendar year that is used for some particular activity
1. a school year