prae-mercor, ātus, 1, v. dep.,
to buy before or beforehand (ante - class.): praemercatur ancillam senex, Plaut. Merc. Arg. 2, 10; id. Ep. 3, 3, 25: ni pretio minus parcerent, eaque praemercarentur, should forestall the markets , Cass. Hem. ap. Plin. 32, 2, 10, § 20.