カバー曲[kabaakyoku] remake of another artist's song (a "cover")
サイン曲線[sainkyokusen] sinusoid
愛唱曲[aishoukyoku] favourite song
委曲[ikyoku] details
一曲[ikkyoku] tune (melody, piece of music)

迂曲[ukyoku] meander
円曲[enkyoku] roundabout way (of speaking or working)
円錐曲線[ensuikyokusen] conic curve
円舞曲[enbukyoku] waltz (composition)
演曲[enkyoku] musical program

歌謡[kayou] song
歌謡曲[kayoukyoku] popular song
神謡集[shinyoushuu] collection of mythology
俗謡[zokuyou] popular song
童謡[douyou] children's song

民謡[minyou] folk song
謡い[utai] noh chanting
謡曲[youkyoku] noh song
俚謡[riyou] ballad
謡う[utau] to sing