The act of adorning or decorating something; elaborate ornamentation or embellishment.
From exornate + -ion suffix. This noun form of the verb exornate follows Latin conventions where -tion becomes the standard action-noun suffix.
In Renaissance rhetoric, 'exornation' was a fancy term for decorative language and elaborate style in speeches—scholars loved giving Greek and Latin names to writing techniques that we now just call 'being flowery!'
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