The state or quality of being a dullard; stupidity or lack of intellectual sharpness.
From dullard + the suffix '-ness' (state or quality). This is an alternative formation to 'dullardism,' using the more common English suffix '-ness' seen in words like kindness and sadness.
English gave us two different ways to describe the condition of being dull—dullardness and dullardism—but most people just say 'stupidity' instead of either fancy word!
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