The external or outer parts of the body or structure (plural: externae); anatomical term for outer surfaces.
From Latin externa, the plural of externum (neuter form of externus 'external'). This is a medical or anatomical Latin term used in scientific nomenclature.
Doctors still use 'externa' in clinical terms like 'otitis externa' (swimmer's ear)—it's the medical way to say 'the outer part' and shows how Latin remains embedded in scientific language.
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