The act of buying and selling goods simultaneously in different markets to gain an immediate profit. Impressive, but tricky.Arbitrage is the simultaneous purchase and sale of the same asset in different markets in order to profit from a difference in its price. The simultaneous purchase and sale of the same securities, commodities, or foreign exchange in different markets to profit from unequal prices. An arbitrage is a transaction that involves no negative cash flow at any probabilistic or temporal state and a positive cash flow in at least one state. Arbitrage is the activity of buying securities or currency in one financial market and selling it at a profit in another. Arbitrage is when an asset (stocks, currencies, etc.) is bought in one market and sold in another for a higher price.