The quality or state of being bad-tempered, quarrelsome, and difficult to deal with.
Derived from cantankerous plus the noun-forming suffix -ness, which transforms adjectives into abstract nouns. This construction became common in English to express the essence or character of a trait.
While most English personality words come from French or Latin, 'cantankerousness' is a wonderfully Anglo-Irish creation—we basically stacked English suffixes onto a mystery word to name a feeling everyone knows!
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