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Webster 1913 Edition
Priapean
Priˊa-pe′an
,Noun.
[Cf. L.
Priapeius
pertaining to Priapus.] (Lat. Pros.)
A species of hexameter verse so constructed as to be divisible into two portions of three feet each, having generally a trochee in the first and the fourth foot, and an amphimacer in the third; – applied also to a regular hexameter verse when so constructed as to be divisible into two portions of three feet each.
Andrews.