Lewis Short
(adj.Subst.) : pĕlăgĭum, ii, v. pelagius, II. B.
* Subst.
* Pĕlăgĭa, ae, f., a kind of pearl-mussel, Plin. 9, 37, 61, § 131.
* Pĕ-lăgĭum, ii, n., purple color, Plin. 9, 38, 62, § 134; 9, 40, 64, § 138.
Charlton T. Lewis, Charles Short, A Latin Dictionary