The quality or state of being difficult or hard to deal with; the condition of being challenging.
From 'difficile' (Latin 'difficilis') combined with '-ness,' an Old English suffix creating abstract nouns for qualities. Latin 'difficilis' means difficult, from 'dis-' (not) and 'facilis' (easy).
While 'difficulty' is standard, 'difficileness' appears in older medical and philosophical texts to emphasize just how inherently problematic or stubborn something truly is.
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