Two hundred pennyworth of bread. The penny, or "denarius," was the chief Roman silver coin, worth about eight-pence halfpenny. Upon the breaking up of the Roman empire, the states which arose upon its ruins imitated the coinage of the old imperial mints, and in general called their principal silver coin the "denarius."
Thus the denarius found its way into this country through the Anglo-Saxons, and it was for a long period the only coin. Hence the introduction of the word into the Authorized Version. Two hundred pennyworth would be of the value of nearly seven pounds.
But considering the constant fluctuation in the relation between money and the commodities purchased by money, it is in vain to require what number of loaves the same two hundred denarii would purchase at that time, although it was evidently the representation of a large supply of bread.