GNU Collaborative International Dictionary of English

Found one definition

1.       
   Rationalism (răshˈŭn‑al‑ĭz'm), n. [Cf. F. rationalisme.]
   1. (Theol.) The doctrine or system of those who deduce their religious opinions from reason or the understanding, as distinct from, or opposed to, revelation.
   
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   2. (Philos.) The system that makes rational power the ultimate test of truth; -- opposed to sensualism, or sensationalism, and empiricism.  Fleming.
   
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