What does arbitrage mean?
The definition of arbitrage
Ar”bi*trage, n.
Etym: [F., fr. arbiter to give judgment, L. arbitrari.]

1 Judgment by an arbiter; authoritative determination. [Archaic]
2 (Com)
A traffic in bills of exchange (see Arbitration of Exchange); also, a traffic in stocks which bear differing values at the same time in different markets.