Devilish or wicked behavior; devilishness; mischievous or malevolent conduct.
From Latin devilitas or modeled on 'civility' (from Latin civilitas). This word is rare and archaic, likely a back-formation or imitation of '-ity' suffix words like civility, brutality, and mentality.
This is an almost-never-used word that shows language's unused potential—English could easily say 'devility' instead of 'devilishness,' and it would follow all the rules, but it just never caught on. Language is full of paths not taken.
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