Plural of abnormity; multiple instances of things that are abnormal, unusual, or structurally irregular.
From abnormity (from Latin abnormis meaning 'away from normal') + -ies (plural suffix). Abnormity itself comes from ab- + norma, making this the plural form of an older version of abnormality.
Abnormities is the older, more formal term that doctors and naturalists used centuries ago—reading Victorian medical texts, you'll find them obsessed with cataloging and displaying abnormities as curiosities and signs of nature's infinite variation.
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