noun, na-adjective
inhumanity; atrocity; abominable cruelty
Strong literary or formal term for extreme cruelty and inhumanity, often used in descriptions of war crimes, brutal acts, or severe moral condemnation.
その独裁者の残酷非道な行為は歴史に刻まれている。
The dictator's atrocious acts are etched in history.
戦争の残酷非道さを伝える記録が展示されている。
Records conveying the inhumanity of war are on display.
A yojijukugo combining 残酷 (cruelty) and 非道 (inhumanity, wickedness). The exact historical derivation is uncertain, but it follows a common pattern of pairing synonymous or complementary kanji compounds for emphasis.