Lewis Short
auctārĭum (noun N) : augeo
* An addition or augmentation of a definite measure: auctarium dicebant antiqui, quod super mensuram vel pondus justum adiciebatur, Paul. ex Fest. p. 14 Müll.: Eu. Tanti quanti poscit, vin tanti illum emi? Ch. Immo auctarium Adicito, Plaut. Merc. 2, 4, 23.
Charlton T. Lewis, Charles Short, A Latin Dictionary