disenroll

Example:He enrolled himself in the first-year physics class this semester.

Definition:To register or admit into an educational institution; to formally enroll.

Example:The young man enlisted in the military after graduating from high school.

Definition:To engage as a soldier, especially by signing a formal agreement.

Example:Hundreds of students registered for the upcoming semester’s courses.

Definition:To enroll in a course, school, or other similar institution or program.