The state or quality of being continual; the character of being constant, repeated, or uninterrupted.
From continual plus -ness suffix. Continual comes from Latin continualis. The -ness suffix is Old English, the most productive way to nominalize adjectives in English.
The continualness of background noise in cities literally rewires your brain's attention system—your auditory cortex learns to filter it, which is why silence in the countryside feels so shocking to urban dwellers.
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