The quality of being arrogant; excessive pride, self-importance, or an overbearing sense of one's own superiority.
From 'arrogant' (from Latin 'arrogans,' meaning claiming or presuming) plus '-ness' (forming abstract nouns of quality). The root suggests someone who 'arrogates' or claims more than they deserve.
Arrogantness is actually connected to 'arrogate'—both come from the same Latin root meaning to claim something unfairly for yourself, so arrogant people are basically those who claim credit, respect, or importance they haven't earned.
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