Contronyms: Words that are their own opposites

From Mental Floss, 14 Words That Are Their Own Opposites:

Here’s an ambiguous sentence for you: “Because of the agency’s oversight, the corporation’s behavior was sanctioned.” Does that mean, 'Because the agency oversaw the company’s behavior, they imposed a penalty for some transgression' or does it mean, 'Because the agency was inattentive, they overlooked the misbehavior and gave it their approval by default'? We’ve stumbled into the looking-glass world of “contronyms”—words that are their own antonyms.

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