ra‧tion‧al‧is‧m AC /ˈræʃənəlɪzəm/ noun [uncountable]
[Word Family: noun: rationality ≠ irrationality, rationale, rationalism, rationalist, rationalization; adjective: rational ≠ irrational, rationalist; verb: rationalize; adverb: rationally ≠ irrationally]
technical the belief that your actions should be based on scientific thinking rather than emotions or religious beliefs:
philosophers who accept scientific rationalism

[TahlilGaran] Dictionary of Contemporary English ▲