Webster's Revised Unabridged Dictionary · 1913

Pentamerus

Pentamerus , noun

[New Latin See Pentamerous.]

(Paleontology) A genus of extinct Paleozoic brachiopods, often very abundant in the Upper Silurian.
Collocations (1)
Pentamerus limestone (Geology) , a Silurian limestone composed largely of the shells of Pentamerus.