The quality or state of being bright, loud, or excessively showy in a way that is unpleasant or offensive.
From garish plus -ness (noun-forming suffix creating abstract nouns from adjectives), allowing the quality itself to become a countable concept.
Words ending in -ness let us talk about qualities as things—'garishness' turns an adjective into a noun, which is why poets can say 'the garishness offended me' instead of just 'it was garish.'
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