dĭaerĕsis

is, f.
I. In gram., the dividing of one syllable into two, as aquaï for aquae, Serv. ad Verg. A. 7, 464.—
II. In rhet., a figure, pure Lat. distributio, distribution, Jul. Rufin. 21, p. 242.
Lewis & Short
A Latin Dictionary, 1879
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