Bioinformatics is the emerging field involving the application of computer methods to the storage and analysis of genomic and proteomic sequences and structures.This dictionary describes about ninety significant terms and concepts in Bioinformatics. Descriptions range from a few sentences to a few paragraphs each. The terms described are specific to bioinformatics; molecular biology or statistical concepts not known to the author to be used significantly in bioinformatics (to date) are excluded.