also: かせい
noun, noun which may take the genitive case particle 'no'
Primarily a music term referring to the combination of simultaneously sounded musical notes to produce chords and chord progressions. Can also be used metaphorically for harmonious agreement.
この曲の和声はとても美しい。
The harmony of this piece is very beautiful.
和声学を学ぶために音楽学校に通
I attend a music school to study harmony.
Compound of 和 (wa, 'harmony, Japanese') and 声 (sei, 'voice, sound'). The reading わせい is the standard Sino-Japanese on'yomi combination; かせい is an older or alternative on'yomi reading.