お七夜[oshichiya] name-giving ceremony
七つ[nanatsu] seven
七つの海[nanatsunoumi] the seven seas
七屋[nanatsuya] pawnshop
七回忌[shichikaiki] seventh anniversary of a death

七角形[shichikakkei] heptagon
七曲がり[nanamagari] tortuous or spiral (path)
七月[shichigatsu] July
七賢[shichiken] the Seven Wise Men (of Confucius's Analects)

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