1) An act of atrocious cruelty 2) An inhuman or inhumane act 3) Cruelty 4) French word used in English 5) Inhumaneness 6) Quality 1) Atrociousness 2) Atrocity 3) Barbarism 4) Barbarity 5) Barbarousness 6) Cruelty 7) Heinousness 8) Inhumaneness 9) Unmercifulness 
• (n.) The quality or state of being inhuman; cruelty; barbarity.
In`hu·man'i·ty noun ; plural Inhumanities . [ Latin inhumanitas : confer French inhumanité .] The quality or state of being inhuman; cruelty; barbarity. « Man's inhumanity to man Makes countless thousands mourn.» Burns. 
inhumanity 1. Lack of pity or compassion. 2. An inhuman or cruel act.
the state or quality of being inhuman or inhumane; cruelty. · an inhuman or inhumane act.