an outward or token appearance or form that is deliberately misleading; "he hoped his claims would have a semblance of authenticity"; "he tried to give his falsehood the gloss of moral sanction"; "the situation soon took on a different color"
(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"