Supreme; of a surpassing quality or quantity.(adjective)
A coronation.(noun)
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Use "crowning" in a sentence
"Maida and Beechy had already been for a walk with Sir Ralph and Mr. Barrymore, who had taken them up by a labyrinth of wooded paths to an old ruined castle which they described as crowning the head of the promontory."
"D'Souza began his storied career with his own vision, as he climbed the ranks from a secretary to the Archbishop studying architecture, to an associate pastor in Malton, a pastor in Don Mills, and then to what he calls his crowning achievement - the building of the St. Francis church on Mavis Rd. from the ground up in 1999."
"Her biggest crowning is the constant defending and making excuses for her husband."