The quality or state of being burdensome; the degree to which something is difficult or oppressive.
From 'burdensome' plus the noun-forming suffix '-ness,' which creates abstract nouns from adjectives. This suffix has Old English roots and is the most productive way to nominalize adjectives.
Burdensomeness is a word within words—it takes burden, adds an adjective suffix, then adds a noun suffix, creating an abstract quality we can discuss and measure without a concrete burden in sight!
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