CRUX
crux, crux of the matter
(noun) the most important point
Source: WordNet® 3.1
Etymology
Noun
crux (plural cruxes or cruces)
The basic, central, or essential point or feature.
Synonyms: core, gist, Thesaurus:gist
The critical or transitional moment or issue, a turning point.
A puzzle or difficulty.
(climbing) The hardest point of a climb.
(heraldiccharge) A cross on a coat of arms.
Etymology
Proper noun
Crux
(constellation) A distinctive winter constellation of the southern sky, shaped like a cross. It appears in the flags of several countries in Oceania.
Synonyms
• Southern Cross
Source: Wiktionary
Crux (krks), n.; pl. E. Cruxes (-, L. Cruces (kr. Etym: [L., cross,
torture, trouble.]
Definition: Anything that is very puzzling or difficult to explain. Dr.
Sheridan.
The perpetual crux of New Testament chronologists. Strauss.
Source: Webster’s Unabridged Dictionary 1913 Edition