pitiless (part of speech: adjective)
insensitive (part of speech: adjective)
callous, hardhearted, hardened, indifferent, hard, ruthless, dispassionate, insensitive, heartless, objective, tough, detached, unemotional, passive, aloof, numb, cold-blooded, unsympathetic, passionless, cool, blunt, anesthetized, stony, uncompassionate, nonchalant, unconcerned, emotionless, apathetic, hard-boiled
senseless (part of speech: adjective)
- Whether the queen saw the folly of these words, and thought of the proper answer to them,- that a king is a man, like those who cry to him for sympathy, but the moon is not a dog,- we do not know; nor whether she perceived the insolent wickedness of the sentence; but she saw the unfeeling absurdity of writing this to a king and queen who were actually prisoners in the hands of their subjects. - "The Peasant and the Prince", Harriet Martineau.
- This unfeeling separation is but the beginning of their sorrows. - "A Visit To The United States In 1841", Joseph Sturge.
- The object shifted a few inches; Mr. Espalin perceived from the tail of his eye the large, unfeeling muzzle of a sixshooter; beyond it, a glimpse of the forgotten elderly stranger, Mr. Pringle. - "The Desire of the Moth; and The Come On", Eugene Manlove Rhodes.