五ご線せん記き譜ふ法ほう

Meanings

1

noun

five-line staff notation; Western staff notation

Technical music term referring to the standard Western system of writing music on a five-line staff.

musical score, music, note

法method, law, rule

楽がく譜ふ
楽譜 is a general term for any musical score, while 五線記譜法 specifically refers to the five-line staff notation system.
記き譜ふ法ほう
記譜法 is the broader concept of musical notation systems; 五線記譜法 is one specific type.

Compound of 五線 (five lines) + 記譜法 (notation system). The term is a direct description of the Western staff notation system.