Some online business dictionaries can be found through Credo Reference. 

• Dictionary of Accounting
• Dictionary of Business
• Dictionary of Economics
• Dictionary of Finance and Investment Terms

Here are some Oxford dictionaries that are available in print:

• A Dictionary of Accounting -- 657.03 D56112005
• A Dictionary of Business -- 650.03 D5612002
• A Dictionary of Economics -- 330.03 B561d2002
• A Dictionary of Finance & Banking -- 332.03 D5612005

For foreign language business dictionaries; go to Credo Reference. Search for "Bilingual Dictionaries".

• The Business French Dictionary; Peter Collin Publishing
• The Business German Dictionary; Peter Collin Publishing
• The Business Spanish Dictionary; Peter Collin Publishing

For dictionaries covering many subject areas, go to the dictionaries page in the Online Reference Collection guide.

Also; take a look at the following websites:

• Dictionary Link
• Glossary of Insurance Terms
• Investopedia.com
• InvestorWords.com
• Merriam-Webster online
• Money Essentials CNN
• OneLook Dictionaries
• Taxonomy Warehouse