means someone who studies fundamental questions about existence, knowledge, values, reason, and the nature of reality, often through argument rather than experiment.

from From Greek philosophos, literally a "lover of wisdom" — philos (loving) plus sophia (wisdom). Tradition credits Pythagoras with the modest dodge: when called wise (sophos), he supposedly demurred that only gods are wise, while he was merely fond of wisdom. The word traveled through Latin philosophus and Old French into English, where it long covered anyone who pondered nature — "natural philosophers" were what we'd now call scientists.