REPENTANCE

n. remorse about past events, regret for past actions, sorrow about past occurrences

In Biblical Hebrew, the idea of repentance is represented by two verbs: שוב shuv (to return) and נחם nicham (to feel sorrow). In the New Testament, the word translated as 'repentance' is the Greek word μετάνοια (metanoia), "after/behind one's mind", which is a compound word of the preposition 'meta' (after, with), and the verb 'noeo' (to perceive, to think, the result of perceiving or observing). In this compound word the preposition combines the two meanings of time and change, which may be denoted by 'after' and 'different'; so that the whole compound means: 'to think differently after'. Metanoia is therefore primarily an after-thought, different from the former thought; a change of mind accompanied by regret and change of conduct, "change of mind and heart", or, "change of consciousness". One of the key descriptions of repentance in the New Testament is the parable of the prodigal son found in the Gospel of Luke 15 beginning at verse 11.
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Noun
1. remorse for your past conduct
(synonym) penitence, penance
(hypernym) compunction, remorse, self-reproach
(derivation) repent, regret, rue

n. penitence, repentance; return to one's faith

(n.)
The act of repenting, or the state of being penitent; sorrow for what one has done or omitted to do; especially, contrition for sin.