The Life Science Dictionary (LSD) is a versatile database and relevant electronic dictionary complex of medical and life science terms developed by our volunteer researchers, LSD project, since 1993. The most prominent feature of the LSD is that both English and Japanese terms are collected based on the frequency in the corpora of scientific documents, abstracts and textbooks. Here, we describe the current status of LSD services and its original database, together with the historical background and future directions.