[1] : The Collaborative International Dictionary of English v.0.48

rationale \ra`tiona"le\ ra^sh`u^na^l" or
   ra^sh`u^n=a"l-e, n. l. rationalis, neut.
   rationale. see rational, a.
   an explanation or exposition of the principles of some
   opinion, action, hypothesis, phenomenon, or the like; also,
   the principles themselves.
   1913 webster
see also:
rational 

[2] : WordNet (r) 2.0

rationale
     n : law an explanation of the fundamental reasons especially
         an explanation of the working of some device in terms of
         laws of nature; "the rationale for capital punishment";
         "the principles of internal-combustion engines" syn: principle
see also:
principle 

[3] : Moby Thesaurus II by Grady Ward, 1.0

47 moby thesaurus words for "rationale":
   account, allegorization, clarification, cracking, decipherment,
   decoding, demonstration, demythologization, editing, elucidation,
   emendation, enlightenment, euhemerism, excuse, exegesis,
   exemplification, explanation, explication, exposition, expounding,
   grounds, illumination, illustration, justification, light, logic,
   philosophy, pretense, pretext, principle, rational ground,
   rationalization, reason, reason for, reason why, reasoning,
   simplification, solution, stated cause, the big idea, the idea,
   the whatfor, the wherefore, the why, theory, underlying reason,
   unlocking

Rationale >> R Words
Rationale, definition of term: Rationale
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