heinous; treacherous; atrocious
Describes an act that is both a grave betrayal and morally outrageous. Often used in historical or dramatic contexts for treason or extreme villainy.
His heinous and treacherous deeds were etched into history.
大逆非道の罪で裁かれた。
He was tried for the crime of high treason and atrocity.
極悪非道 focuses on extreme wickedness without the element of betrayal; 大逆非道 specifically combines treason with heinousness.
Compound of 大逆 (great treason) and 非道 (unjust, inhuman). The exact historical derivation is uncertain, but the combination emphasizes both betrayal and extreme cruelty.