hear it again

: the most important point

Example sentence:
After beating around the bush for a while, Cameron finally got to the crux of his argument.

Etymology:
Back in ancient Rome, crosses were used for punishment, and the Latin word "crux" meant both "cross" and "torment." English speakers of the 18th century likened trying to solve a difficult puzzle to a painful punishment, and "crux" acquired the meaning of "an unsolvable puzzle or problem." Over time, "crux" also came to be used for a main point or problem that needed discussing. Eventually, its meaning was extended even further, and it came to refer to simply a main or central feature of something.