The act or practice of committing evil or harmful deeds; wicked or immoral conduct or behavior.
Compound word from 'evil' (Old English 'yfel') plus 'doing' (gerund of 'do'), literally meaning 'the doing of evil.' The '-ing' form allows it to function as both noun and activity descriptor, common in Old and Middle English.
The difference between 'evildoing' (the act itself) and 'evildoer' (the person) shows how English lets you focus on either the action or the actor—and interestingly, societies focus on different aspects when assigning blame.
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