tertĭārĭus

a, um, adj.

id.

I. containing a third part.
I. Adj.: stannum, Plin. 34, 17, 48, § 160. —
II. Subst.: tertĭārĭum, ii, n., a third part, a third, Cato, R. R. 95, 1; Vitr. 4, 7, 5.
Lewis & Short
A Latin Dictionary, 1879
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