noun
transcript of results; academic record
Formal document issued by a school or institution listing a student's grades or academic performance.
大学に出願するときは、成績証明書を提出しなければならない。
When applying to a university, you must submit your transcript of results.
成績表 is a more general term for a grade report or report card, often used in primary and secondary education, while 成績証明書 is a formal, official transcript.
Compound of 成績 (grades, results) + 証明書 (certificate, written proof).