The dictionary started in early 1997 and has grown, to contain over 46,000 definitions totalling 17.5 megabytes. Entries are cross-referenced to each other and to related resources elsewhere on the net. It is freely available on the Internet via the World-Wide Web.  OMD is a searchable dictionary created by Dr Graham Dark and contains terms relating to biochemistry, cell biology, chemistry, medicine, molecular biology, physics, plant biology, radiobiology, science and technology. It includes: acronyms, jargon, theory, conventions, standards, institutions, projects, eponyms, history, in fact anything to do with medicine or science.