This is the 17347th most frequent Korean word.
선생을
"선생을" is the accusative form of "선생," meaning "teacher."
In this case, '선생을' is the object complement indicating the recipient of respect from the student.
그 학생은 선생을 존경했습니다.
That student respected the teacher.
Here, '선생을' is used as the object of the sentence referring to 'teacher', emphasizing the action of meeting the teacher.
저는 선생을 만나러 학교에 갔습니다.
I went to the school to meet the teacher.
Here, '선생을' is used to denote the means or medium through which learning occurred.