A stock character in popular fiction; a bumbling scientist working on unlikely ways to save the world, or a villainous one bent on destroying it.(noun)
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Use "mad scientist" in a sentence
"And I did notice Dana, but I was so single-minded then — a mad scientist devoted to my work with tall, statuesque Susan, we were like a small Intercourse Research and Development firm — that it never occurred to me to go out with anyone else, especially my old grade-school friend, the eternally presexual, perpetually cute Dana."