音度 is read as おんど (ondo) and means scale degree.
おんど
ondo
さんどのわおん
common chord
ねいろ
tone color
おんがく
music
おと
Chinese-derived character reading
おん
ね
おんがくか
musician
おんどく
reading (a kanji) by its Chinese-derived pronunciation
おんよみ
on reading
おんしつ
tone quality
いちど
temporarily
こんど
this time