The quality of being copious; abundant supply or large quantity, especially of words, ideas, or materials.
From 'copious' (Latin 'copiosus') plus the suffix '-ness' to create an abstract noun indicating a state or quality of abundance.
The Renaissance admired 'copia' (linguistic abundance) so much that educated Europeans competed to demonstrate their vocabulary mastery—books on rhetoric taught you how to say the same thing fifty different ways, which seems excessive by modern standards.
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