This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

n. The basic, central, or critical point or feature: the crux of the matter; the crux of an argument.

n. A puzzling or apparently insoluble problem.

n. The basic, central, or essential point or feature.

n. The critical or transitional moment or issue, a turning point.

n. A puzzle or difficulty.

n. The hardest point of a climb.

n. A cross on a coat of arms.

n. Anything that is very puzzling or difficult to explain.

n. A cross. See phrases below. Specifically

n. The Southern Cross, the most celebrated constellation of the southern heavens.

n. The cross as an instrument of torture; hence, anything that puzzles or vexes in a high degree; a conundrum.

n. the most important point

n. a small conspicuous constellation in the southern hemisphere in the Milky Way near Centaurus

"Nor does the Latin word crux automatically refer to a cross while patibulum refer to the cross-beam."

constellation   

crux decussata    crux commissa    crux ansata    crux stellata   

crucial   

cruces   

Bucks    Canucks    Luks    Tux    bucks    clucks    deluxe    ducks    dux    flux   

pretiosa    poser    mentiantur    adductus    generatio    dicerem    gemma    notitiam    verumque    minorem