The definition of crux is the central point of something, or is something that seems impossible to solve.(noun)
See crux in Webster's New World College Dictionary
See crux in American Heritage Dictionary 4
cruxnoun pl. cruxes crux·es or cru·ces (kro͞oˈsēz)
Origin: Probably short for Medieval Latin crux (interpretum), torment (of interpreters), from Latin crux, cross.
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