Lewis Short
mēcōnĭum (noun N) = μηκώνιον: .
* Poppy-juice, Plin. 20, 18, 76, § 202; 25, 12, 91, § 142.
* A plant, called also peplis, Plin. 27, 12, 93, § 119.
* The excrements of new-born children, Plin. 28, 4, 13, § 52.
Charlton T. Lewis, Charles Short, A Latin Dictionary