Definition of "monomaniac" [mon•oma•ni•ac]

• A person who is obsessed with a single thing, to the exclusion of other concerns. (noun)
• Focussed on one thing above all others. (adjective)

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• "Nothing could be more just than to class him as a monomaniac, for he was one, if by the word monomaniac we designate every man who is dominated by a fixed idea."
• "I'd be more than happy to see a few more members of Congress with their "monomaniac" commitment to the democratic process."
• "Though "monomaniac" was a little harsh, it wasn't all that unfair, and frankly good for you for being one."