Relating to or occurring at a culmination or highest point; pertaining to the climax of something.
From Latin culmina (peak, summit) + -al (adjective suffix). The root traces to culmen, meaning the highest point of a roof or peak, which evolved into meaning any pinnacle or climax.
Latin builders used 'culmen' to describe the highest point of a roof ridge, and that architectural metaphor expanded so much that now 'culminal' can describe the peak of anything from a career to a musical phrase.
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