[cal.lous] adj [MF calleux, fr. L callosus, fr. callum, callus callous skin] (15c) 1 a: being hardened and thickened b: having calluses
2. a: feeling no emotion b: feeling no sympathy for others -- cal.lous.ly adv -- cal.lous.ness n
[2]callous vt (1834): to make callous