American terms to British

Some important American terms that may not always be understood in Britain, or which have different a different meaning:

Anti-trust
Used to describe laws and regulatory mechanisms that keep markets competitive, for example by preventing the formation of cartels (trusts).
Checking account
Current account
Common stock
Ordinary shares. The term stock is casually used to refer to securities in the US, but not in the UK. The British usage is technically more correct.
CPA
Certified public accountant. Broadly equivalent to a chartered accountant or other accountant belonging to a body whose members may be auditors.
Dow theory
A system of technical analysis based on the the ideas of Charles Dow, founder of the Wall Street Journal and co-founder of Dow Jones & Co.
John Doe/Jane Doe
An unnamed defendant of a a lawsuit. Often used when suing someone whose real identity has not yet been established, for example in cases of anonymous libel or breach of copyright.
Inventory
Stock. The term inventory is also sometimes used in Britain.
Income statement
Profit and loss account.
Leverage
Gearing. The two terms are clearly based on similar metaphors.
Mutual fund
A collective investment vehicle similar to a unit trust or an OEIC.
Operating leverage
Operational gearing
Preferred stock
Preference shares.
Savings and loan association
A financial institution similar to a building society.
Specialist
A market participant with a similar role to a market maker. Differences in regulation and market mechanisms mean that the roles can very different in some ways. What is common across markets is the trade-off of a privileged position in the trading system in return for providing the market with stability or liquidity. The term market maker is also used in the US when appropriate.
Stock
Equity securities
Wall Street
New York's financial district. Equivalent to the City and used as an adjective in the same way: e.g. “Wall Street Analyst”