Word of the Day:

1 : a puzzling or difficult problem

2 : an essential point requiring resolution or resolving an outcome

3 : a main or central feature (as of an argument)

The crux of the city's problem with traffic congestion is that many people find the trains to be unpredictable and don’t trust them to run on time.

"The crux of the problem is that as a person loses weight, especially in more aggressive dieting, the body changes the hormones it's producing, adjusting for the loss in fat reserves, and promoting a stronger urge to eat more and replace the reserves." -- From an article by Rupert Shepherd in Medical News Today, October 26, 2011

More example sentences

In Latin, "crux" referred literally to an instrument of torture, often a cross or stake, and figuratively to the torture and misery inflicted by means of such an instrument. "Crux" eventually developed the sense of "a puzzling or difficult problem"; that was the first meaning that was used when the word entered English in the early 18th century. Later, in the late 19th century, "crux" began to be used more specifically to refer to an essential point of a legal case that required resolution before the case as a whole could be resolved. Today, the verdict on "crux" is that it can be used to refer to any important part of a problem or argument, inside or outside of the courtroom.