The quality or state of being dismal; the degree of gloominess or dreariness.
From dismal + -ness (suffix forming abstract nouns from adjectives). This is the modern preferred formation over 'dismality' for creating the abstract noun.
English speakers consistently choose -ness over -ity for newer abstract nouns, which is why 'dismalness' feels modern while 'dismality' sounds archaic—the language is slowly standardizing its noun-forming tools.
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