Not willing to forgive; harsh and severe without mercy or leniency.
From Old English 'un-' (not) + 'forgive' (from Old English 'forgiefan', meaning to give up or grant). The 'for-' prefix intensified the meaning of 'give,' originally meaning to surrender a claim. Over time it came to mean pardoning offenses.
Interestingly, 'forgive' and 'forget' are linguistically connected through Old English—forgiveness was literally about 'giving away' your right to anger, which is why unforgiveness feels like holding onto something heavy.
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