A person or thing that makes someone or something weaker or less strong.
From enfeeblement with the agent suffix -er, which typically creates nouns meaning 'one who does' the action. This word names whoever or whatever causes the weakening.
Agent nouns like 'enfeebler' are fascinating because they can refer to people (a bully is an enfeebler of confidence) or abstract forces (disease is an enfeebler of health), collapsing different types of causation into one word.
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