Synonyms of the word 
HEARTLESSNESS → COLDHEARTEDNESS - HARDHEARTEDNESS - UNCONCERN
heartlessness
- n. the characteristic of being heartless.
coldheartedness
- n. Alternative spelling of cold-heartedness.
hardheartedness
- n. (uncountable) The state of being hardhearted.
- n. (countable) A hardhearted thought or act.
unconcern
- n. (nonstandard, obsolete) indifference or lack of concern.
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