Our comprehensive glossary explains many of the terms commonly used in the international markets.

OBV (On Balance Volume)

The calculation is an accumulated running total of the of volume calculated from the following explanation. If the stock's share price closes above the previous day's or periods close, then all the volume traded during that period is added to the total OBV. If the stock's share price closes below the previous periods close, then all the volume traded in that period is subtracted from the total OBV.

Offer price

The price at which you can buy a specified instrument. For Forex trading, it is the price at which you can buy the trade/base currency (quoted first) by selling the price currency of the pair. For example, if you buy EURUSD 100,000, you are buying euros 100,000 against US dollars.

One-cancels-other (O.C.O.) order

One-cancels-other orders really consist of two orders. If either of the orders is executed because its market conditions have been met, the related order is automatically cancelled.

Open interest

The total number of purchased or sold lots in a particular type of exchange traded contract that have not yet been offset, i.e. sold off or bought back.

Open order

An order still pending or on the books to buy or sell security, but not yet executed. An open order will remain in effect until it is either executed or cancelled or for a period of two weeks, at which point it lapses. If orders are required to remain open for more than two weeks, they can be placed "GTC" (good till cancelled).

Open position

A position in a currency that has not yet been offset. For example, if you buy USDJPY 100,000, you have an open position in USDJPY until you offset it by selling USDJPY 100,000.

Option holder

The owner of a option


A trade order to buy or sell a specified instrument. Limit and Stop orders are the main types.

Order duration

The duration for which the order is valid. See Day Order (DO) and Good till Cancelled (GTC) for details.

Ordinary share capital

Capital of a company represented by the number of its ordinary shares.

Ordinary shares

Also sometimes called "equity" shares, these are fixed shares, which share in the profits and risks of the company. Unlike the fixed dividend paid to preference shareholders, the ordinary dividend is decided by the directors, and is dependent on the company's profits. If the company is liquidated, the ordinary shareholders share out the proceeds after the creditors and preferential shareholders have been paid out. For these reasons, ordinary share prices tend to be far more volatile than preference shares, giving opportunities for capital gains. Most of the shares published in the newspaper are ordinary shares.


An indicator that determines when a market is in an overbought or oversold condition. When the oscillator reaches an upper extreme, the market is overbought. When the oscillator line reaches a lower extreme, the market is oversold.

Other collateral

Instruments that are not tradable online. For example, bonds and other positions that are transferred from another bank.

Out of the money

An Option that has no intrinsic value. If an Option expires out of the money, it is worthless. An out-of-the-money Option is a call Option with a strike price that is higher than the current market level, or a put Option with a strike price that is below the current market price.


A particular price level that, if hit during the life of an Option, immediately invalidates the Option.

Over the counter (OTC)

A trade that is negotiated between two parties without the use of an exchange. For example, a security that is not traded on an exchange is known as an OTC security. It is a market where commodities and instruments are traded directly between two parties, for example, between an investment bank and a client. This is different from trading on a public exchange, which is an open market place. Over-the-counter products can be tailored to individual clients whereas exchanges trade standardised contracts. A large over-the-counter market has grown up in, for example, Forex and Forex Options.


This occurs where the applications for a new issue of shares exceed the number of shares available for issue. This often happens because the shares are offered to the public at a price below their inherent value and people obtaining the shares can make an immediate "stagging" profit when the shares are listed


A technical condition that occurs when prices are considered too high and susceptible to a decline.

Overbought / Oversold indicator

An indicator that attempts to define when prices have moved too far and too quickly in either direction.


A technical condition that occurs when prices are considered too low and ripe for a rally.