Plural of academia; multiple academic institutions, communities, or the collective worlds of higher learning.
From academy (Latin Academia) plus the plural suffix -s. 'Academia' itself is a Latin form of 'academe' often used in formal institutional contexts, and 'academias' is its straightforward plural.
The word 'academia' is particularly interesting in Romance languages, which kept it closer to the Latin form, while English gradually simplified to 'academe'—each language preserved different versions of Plato's ancient garden.
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