Sestertius

Sestertius (literally, "that which contains two and a half," from semis (= semi), "half," and tertius, "third"), a Roman coin, which ongmally contained 2-1/2 asses, being a quarter of the denarius, which contained 10 asses. When the denarius was made equivalent in value to 16 asses, that of the sestertius became 4 asses. The sestertius was worth about 2d. of our money. The sestertium, a money of acconnt, was equal to a thousand sestertii.