离校 (lí xiào) literally means 'leave school' — 离 (lí) means 'to depart from' or 'to separate from', and 校 (xiào) is short for 学校 (xuéxiào), meaning 'school'. Together, the phrase refers to the formal act of completing one's studies and departing from an educational institution, most commonly used to mean 'to graduate' — especially from high school or university. It implies official completion of a program, not just skipping class or taking a temporary break.

This term is neutral in register and appears frequently in academic contexts, official documents, graduation announcements, and conversations about education timelines. While it can technically refer to leaving school for any reason (e.g., expulsion or withdrawal), in everyday usage it overwhelmingly carries the positive, milestone connotation of graduation. It’s often paired with time markers like 上个月 (last month), 今年 (this year), or after graduating (毕业后).