A Dictionary for Science - Compiled by A. J. Noice, BSc. Hons. Forensic Science, and edited by W. K. Griffiths, BSc. Hons. Forensic Science and Biology.
General Chemistry Online: Glossary - Searchable and browsable by topic or letter. Part of General Chemistry Online! by Fred Senese at Frostburg State University.
Physical Organic Chemistry Terms - Indexed glossary of terms collected by the International Union of Pure and Applied Chemistry.