Upper edge - Ageha

...The musical form is usually composed of three sections. The first section begins with a low note, repeats a mid-low melody, and ends with a low note. The second section begins with a mid-low melody, repeats the same mid-low melody, and ends with a low note again. The third section begins with a high note, but the first one or two lines are sung by the shite and waki (this is called kamigeha), repeats a high-middle melody, and ends with a drop to a low note. This three-section type is the most common, but there are also two-section types consisting of the first and third sections (such as Matsukaze) and one-section types consisting of only the first section (such as Ama)....

*Some of the terminology explanations that mention "Kamigehata" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…楽式は普通3節から成り，第1節は低音で始まって中下旋律をくり返したのち下音で終わり，第2節は中音から始まって，同じく中下旋律をくり返したのち再び下音で終わる。第3節は上音で始まるが，その初めの1～2句だけをシテ，ワキなどの役が謡い(これを〈上ゲ端（は）〉と呼ぶ)，上中旋律をくり返したのち下音に下って終わる。この3節型がもっとも例が多いが，ほかに，第1節･第3節から成る2節型(《松風》など)や，第1節のみの1節型(《海人（あま）》など。…

※「上ゲ端」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報