The quality of being dear; the state of being beloved or cherished, or alternatively, the quality of being expensive or costly.
From 'dear' (Old English 'deore') combined with the suffix '-ness' (from Old English 'nes', used to create abstract nouns from adjectives).
Most words evolve toward one meaning, but 'dearness' stayed connected to both the affectionate 'dear one' and the economic 'dear/expensive'—medieval people talked about the 'dearness of bread' during famines with the same word for loving relationships.
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