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c.1300, "characterized by intellectual depth," from Old French profund (12c., Modern French profond), from Latin profundus "deep, bottomless, vast," also "obscure; profound; immoderate," from pro- "forth" (see pro-) + fundus "bottom" (see fund (n.)). The literal and figurative senses both were in Latin, but English, having already deep, employed this word primarily in its figurative sense. Related: Profoundly.