Agio
Charge made when cash is given for paper currency, or one currency is exchanged for another.
American option
An option that can be exercised anytime during its life, unlike European options.
Anchor currency
In a currency board system, countries fix their exchange rate to a defined anchor currency.
Arbitrage
Taking advantage of divergences in exchange rates in different money markets by buying a currency in one market and selling it in another market.
Ask price
The price at which a bank will sell forex or lend money.
At the money
An option is at the money if the strike price of the option equals the market price of the underlying security.
At-the-money
An option is "at-the-money" if the price of the underlying instrument corresponds to the strike price or comes very close to it.