The quality or state of being emblematic or symbolic.
From emblematical plus the suffix -ness, which comes from Old English and forms abstract nouns from adjectives. This creates a noun meaning 'the quality of being [adjective].'
The awkwardness of 'emblematicalness'—with its four syllables of -ical-ness stacked together—shows why English speakers naturally prefer 'emblematicity' or simply 'emblematic quality' instead, revealing how our brains optimize for pronunciation.
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