The quality or state of being average; ordinariness or the condition of being neither particularly good nor bad.
From average plus -ness (suffix forming nouns from adjectives). The concept of measuring 'averageness' as a distinct quality only became common as mathematics and statistics developed in the modern era.
There's something philosophical about 'averageness' as a noun—it implies that being in the middle is itself a measurable, distinct thing. Marketing companies have spent billions trying to understand and sell to the 'average consumer,' making ordinariness one of the most profitable things to study.
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