1. Feelings of extreme heartlessness
   - cruelty, pitilessness, ruthlessness 
2. Inhumaneness evidenced by an unwillingness to be kind or forgiving
   - unmercifulness

Derived forms: mercilessnesses

See also: merciless

Type of: coldheartedness, hardheartedness, heartlessness, inhumaneness, inhumanity

Antonym: mercifulness

• non-slave
• non-standard speech
• non-U
• Non-Ugric
• non-volatile storage
• non-water-soluble
• non-white
• non-zero
• nona-
• nonabsorbency
• nonabsorbent
• nonabsorptive
• nonacceptance
• nonaccomplishment
• nonachievement
• nonachiever
• nonacid
• nonadaptive
• nonaddictive
• nonadhesive
• nonadjacent
• nonadsorbent
• nonadsorptive
• nonage
• nonaged