say it: rash-uh-NAL
rationale is a noun meaning "(law) an explanation of the fundamental reasons (especially an explanation of the working of some device in terms of laws of nature)". It carries one recorded sense.
(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”
law
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for rationale come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.