remorse
definition
a deep feeling of regret or guilt for a wrong committed
example
After realizing the impact of his actions, he felt a deep sense of remorse for the pain he had caused.
synonyms
regretguiltsorrow
word origin — Middle English, from Old French 'remorse' meaning 'pity,' based on Latin 'remorsus' (a biting back, regret), from 'remordere' (to bite back).