Encyclopedia of Life (EOL) is a free online resource with pages of taxa. The entire taxonomic position is displayed and an easy-to-navigate interface covers all relevant information of an organism: Morphology, Ecology, Genetics, etc. You can enter a common or scientific name in the general search page or from Advanced Search page that allows you to select filters.
Find definitions of biology terms in these resources:
The Basics of Biology by Carol Leth Stone(Gale eBook) This volume provides students an introduction to the science of biology. It details the history of biology, as well as many of the field's basic theories and concepts for students. It demonstrates the modern tools and techniques that biologists use today.
Dictionary of Biology by W. G. Hale; J. P. Margham; Venetia A. Saunders(Credo eBook) The third edition of the Collins Dictionary of Biology has been completely revised and updated to take in the latest developments on biology from the Human Genome Project to advancements in cloning. The bestselling dictionary of biology, designed for advanced school students, undergraduates, and all who have an interest in the life sciences.