The quality or state of being featureless; the absence of distinctive characteristics.
From featureless plus the noun-forming suffix -ness (Old English '-ness'), creating an abstract noun that names the quality itself rather than just describing something that has it.
The concept of featurelessness is actually important in psychology and art—blank spaces and minimal designs can be calming or unsettling depending on context, which is why meditation spaces often embrace it while dystopian novels use it to create dread.
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