English Reference

Word

crux

US/ˈkɹəks/

UK/kɹˈʌks/

Definition

n. the most important part of a problem or an argument. It is the central point that everything else depends on.

n. the most essential or decisive point of an issue or argument. Often used to identify the core element that must be resolved to reach a conclusion.

Examples

“The crux of the matter is that we lack funding.”

“After hours of debate, the committee finally reached the crux of the problem: the software was simply incompatible with the old hardware.”

“While the lawyers argued over minor procedural details, the judge reminded them that the crux of the case remained whether the defendant had acted with clear intent.”

Examples

simple

“The crux of the matter is that we lack funding.”

contextual

“After hours of debate, the committee finally reached the crux of the problem: the software was simply incompatible with the old hardware.”

complex

“While the lawyers argued over minor procedural details, the judge reminded them that the crux of the case remained whether the defendant had acted with clear intent.”

Usage

Usually appears in the singular form, often in the phrase 'the crux of the matter'.

Real-World Examples

“Clancy’s mental health has become the crux of the case.”
Toronto Sun · 27 Aug 2026
“His comments reveal the crux of the matter.”
The Conversation · 26 Aug 2026

Etymology

Learned borrowing from Latin crux (“a cross”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

Related words

This entry

Level
C1 · Advanced
Frequency
Occasional
Updated

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English Reference