What does crux mean?
The crux of something is the single point on which everything else depends — the decisive core of an argument, problem, or situation. Borrowed directly from Latin, where crux means 'cross,' the word entered English in the early eighteenth century to describe a puzzling difficulty before settling into its modern sense of the essential issue. Today it appears most often in phrases like 'the crux of the matter,' signaling that a speaker has cut through detail to what truly matters. Because it names the pivotal point rather than peripheral concerns, crux conveys precision and analytical clarity, making it especially valued in journalism, law, philosophy, and everyday discussion where identifying what really counts is the whole game.
The most important or decisive point of an issue, problem, or argument.
"Money was never the crux of their disagreement; trust was."
Almost always preceded by 'the' and followed by 'of.'
A particularly difficult or perplexing passage in a literary or historical text that requires interpretation.
"Editors have long treated the corrupted line as the play's chief textual crux."
Chiefly used in textual criticism and classical scholarship.
The anglicized plural 'cruxes' is standard; the Latinate plural 'cruces' (pronounced /ˈkruːsiːz/) survives mainly in scholarly writing about texts.
"The chapter examines several cruces in the poem's transmission history."
Crux is literally Latin for 'cross' — so when you get to 'the crux of the matter,' you're getting to its very crossroads.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of crux
Crux comes directly from Latin crux, meaning 'cross,' specifically the cross of execution. In English from around the early eighteenth century it first meant a puzzling or problematic point — as if one were 'nailed to a cross' by a difficulty — before developing its dominant modern sense of the decisive point of an issue. It shares this Latin root with crucial, crucify, crusade (via Latin cruciata), and cruciform.
How crux is actually used
Crux is almost always used with the definite article — 'the crux' — and typically followed by 'of': 'the crux of the matter.' It carries a slightly formal, analytical register, common in journalism, academic writing, and debate. The plural is usually 'cruxes,' though the Latinate plural 'cruces' appears in scholarly contexts.
Easily confused with crux
Cruces is not a separate word but simply the Latin plural of crux, sometimes used in scholarly English instead of 'cruxes'.