Auto-antonym

n. word having two opposing meanings such as the word "dust" which means " to remove dirt or dust and also means "to sprinkle" or "scatter dust"

An auto-antonym (or, more properly, autantonym), or contronym (sometimes misspelled contranym) is a word with a homonym that is also an antonym. Variant names include antagonym, Janus word, and self-antonym. It is a word with multiple meanings, one of which is defined as the reverse of one of its other meanings.
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