The quality or state of being atypical; the condition of not conforming to a type or standard.
From 'atypical' + suffix '-ity' (from Latin '-itas,' denoting a state or quality). The word builds on 'atypic' with the formal nominal suffix to create an abstract noun describing the property of being non-standard.
This is the kind of word that feels very formal and technical—you'd encounter it in academic papers about psychology or medicine when researchers need to talk about how oddly something is behaving. It's that jargony-but-precise style that makes scientific writing sound impressive but also sometimes impossible to understand.
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