Compunctiously is an adverb that describes feeling guilt or remorse for a wrongdoing. There are several synonyms for this word, such as regretfully, remorsefully, penitently, contritely, apologetically, ruefully, and sorrowfully. These words convey a sense of deep regret and a desire to make amends for one's actions. In literature, these words are often used to describe a character's emotional state when they realize the impact of their actions on others. These synonyms can also be used in everyday situations, such as apologizing for a mistake made at work, or expressing regret for hurting someone's feelings.