Bonsai with remarkably twisted trunks are called Nejikan (twisted trunks) while those that are even more twisted or coiled like a snake are called Bankan style.
幹が著しく捩れているもの、または捩れて成長する性質のものを捩幹と呼び、幹が更にネジれた状態、あたかも蛇がとぐろを巻いた様な樹形を蟠幹と呼ぶ。