The quality of being ordinary, unoriginal, or lacking special distinction; the state of being trite or lacking novelty.
From 'commonplace' + -ness (noun-forming suffix). This compounds the medieval book-keeping term with a Germanic suffix to describe the abstract property of being unexceptional.
The 'commonplaceness' of internet memes is what makes them work—they succeed precisely because they're familiar and easy to understand. A truly original meme usually fails because it's too strange to be viral.
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