crux of the matter

Idioms  

1. Also, heart of the matter. The basic, central or critical point of an issue. For example, In this trial the bloodstains represent the crux of the matter, or We think the second clause is the heart of the matter. Although crux is Latin for “cross,” in English it means “difficulty” or “puzzle,” and it is from the latter that this expression is thought to be derived. The variant employs heart in the sense of “a vital part” (as it is in the body). The first term dates from the late 1800s, the variant from the early 1500s.

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Example Sentences

And this is the crux of the matter.

From BBC • Jan. 6, 2026

“We all know that the crux of the matter is how funders and recruitment, tenure, and promotion committees evaluate researchers.”

From Science Magazine • Apr. 16, 2024

How AI and the Lure of Efficiency Threaten Human Writing, she dives into the crux of the matter: If we hand over the written word to AI, what will we lose?

From Scientific American • Sep. 29, 2023

And herein lies the crux of the matter.

From Los Angeles Times • May 24, 2023

Six weeks of listening to Francis had made me realize that the crux of the matter was whether Rosy’s new X-ray pictures would lend any support for a helical DNA structure.

From "Double Helix" by James D. Watson