The word "cold-fistedly" refers to someone who acts in a cold, unfeeling, and indifferent manner. Synonyms for this word would include "heartlessly," "cruelly," "callously," "uncharitably," and "unsympathetically." These words all convey a sense of emotional detachment and a lack of concern for others. Other synonyms could include "implacably," "unforgivingly," and "ruthlessly," which suggest a harsh and unrelenting severity in one's actions or attitudes. Ultimately, whether we use "cold-fistedly" or one of its many synonyms, we are describing an individual who is lacking in empathy, compassion, and kindness.