The simultaneous buying and selling of a security at two different prices in two different markets , resulting in profits without risk . Perfectly efficient markets present no arbitrage opportunities. Perfectly efficient markets seldom exist, but, arbitrage opportunities are often precluded because of transactions costs.
ARBITRAGE
Meaning of ARBITRAGE in English
Campbell R. Harvey. Hypertextual finance English glossary. Английский словарь гипертекстовых финансов. 2012