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what is meant by "crucks od life"
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See more here: crux definition | Dictionary.comcrux
/krʌks/ Show Spelled Pronunciation [kruhks] Show IPA Pronunciation
–noun, plural crux⋅es, cru⋅ces /ˈkrusiz/ Show Spelled Pronunciation [kroo-seez] Show IPA Pronunciation .
1. a vital, basic, decisive, or pivotal point: The crux of the trial was his whereabouts at the time of the murder.
(It's the root of the word 'crucial'.)