InvestorWords  - searchable financial glossary with terms listed by subject as well. Offers partnering options.

American Banker Online: Banker's Glossary - provides definitions and explanations of common terms for banking professionals.

American Business Jargon Dictionary - dictionary of American business jargon from above board to zilch, zip, and zombie bonds.

Australian Financial Review Dictionary of Investment Terms

Business Glossary - courtesy of washingtonpost.com.

Finance-Glossary.com - cross-referenced, keyword searchable terms with links to related streaming video, events, and web sites.

Financial Glossary - long list of over 2,500 financial terms compiled by Campbell R. Harvey at Duke University.

MoneyWords - glossary for business, financing, and real estate.

Offshore Glossary

Quicken.com Glossary

TermFinance - explanations of financial terms in English, French, German, and Italian.