CRUX Meaning of CRUX in English [ krʌks ]■ noun ( plural ~es or cruces 'kru:si:z ) ( the ~ ) the decisive or most important point at issue. ↘a particular point of difficulty.OriginC17: from L., lit. 'cross'. Concise Oxford English vocab. Сжатый оксфордский словарь английского языка. 2004