This is the 7783rd most frequent Chinese word.
開學
"開學" means "to start school" or "the beginning of a new school term."
In this sentence, '開學' is used to denote the start of a new academic term.
新的學期今天正式開學了。
The new semester officially starts today.
Here, '開學' refers to the act of joining the academic activities at the beginning of the academic year.
我今年秋季要去大學開學。
This fall, I will attend the university for the start of the semester.
In this context, '開學' is used to illustrate the general time frame when the semester begins.