Chemical Safety Information - Glossary
A resource developed by the Physical and Theoretical Chemistry Laboratory at Oxford University. The resource comprises a clickable alphabetical list of terms related to chemical safety and hazardous materials. Each term is concisely defined and explained.
http://ptcl.chem.ox.ac.uk/MSDS/glossary/GLOSSARY.html

General Chemistry Glossary
A searchable, crosslinked collection of over 1000 chemical terms and abbreviation with audio pronunciations. Part of General Chemistry Online by Fred Senese at Frostburg State University.
http://antoine.frostburg.edu/chem/senese/101/glossary.shtml

Glossary of Archaic Chemical Terms
This glossary was developed based on terms that the author came across in the course of reading classic chemistry papers. It has been expanded to include formulas and structures for some common acid-base indicators and vitamins, as well as some other interesting non-systematic chemical terms.
http://web.lemoyne.edu/~giunta/archema.html

UNCChem Glossary
This glossary contains fundamental terms of chemistry that would be used in freshman level chemistry classes. Click on the first letter of the term to find the word you want to look up.
http://www.shodor.org/UNChem/glossary.html