This is the 7123rd most frequent Korean word.
제출
"제출" means "submission."
Here '제출' refers to the act of turning in an assignment or homework.
숙제를 오늘까지 제출해야 합니다.
The homework must be submitted by today.
'제출' in this sentence is used to describe delivering a document digitally.
보고서를 이메일로 제출했습니다.
I submitted the report via email.
In this context, '제출' is used to indicate the action of officially giving a document to a superior.