Nostrum \Nos"trum\ (-tr[u^]m), n.; pl. {Nostrums} (-tr[u^]mz). [Neut. sing. of L. noster ours, fr. nos we. See {Us}.] 1. A medicine, the ingredients of which are kept secret for the purpose of restricting the profits of sale to the inventor or proprietor; a quack medicine. 2. Any scheme or device proposed by a quack. The incentives of agitators, the arts of impostors and the nostrums of quacks. --Brougham.