Mawson, C.O.S., ed. (1870–1938). Roget’s International Thesaurus. 1922.

Class VI. Words Relating to the Sentient and Moral Powers
Section III. Sympathetic Affections
3. Special Sympathetic Affections

914a. Pitilessness.

   NOUN:PITILESSNESS &c. adj.; inclemency, inexorability, inflexibility, incompassion [rare], hardness of heart; want of pity [See Pity]; severity [See Severity]; malevolence [See Malevolence].
   VERB:BE PITILESS &c. adj.; turn a deaf ear to; claim one’s “pound of flesh” [M. of Ve]; have no -, shut the gates of- mercy [See Pity]; give no quarter.
   ADJECTIVE:PITILESS, merciless, ruthless, bowelless; unpitying, unmerciful, inclement; grim-faced, grim-visaged; un- compassionate, incompassionate [rare], uncompassioned; inflexible, relentless, inexorable; unrelenting [See Revenge]; harsh [See Severity]; cruel [See Malevolence].