Pronunciation: (kruks), [key]
—pl. crux•es, cru•cesPronunciation: (krOO'sēz). [key]
1. a vital, basic, decisive, or pivotal point: The crux of the trial was his whereabouts at the time of the murder.
2. a cross.
3. something that torments by its puzzling nature; a perplexing difficulty.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.