The Grammatical Dictionary of Botanical Latin is intended to help taxonomists prepare Latin diagnoses and descriptions of new taxa, and to read certain published Latin scientific literature, primarily in botany. It is a compendium from many sources of botanically useful words, enhanced with examples of usage, and interspersed with annotations, explanations, observations, and grammatical guides. The Dictionary is also freely available to the botanical community online as a searchable database. It is presently only partially finished. The Dictionary also supports the present requirement of the International Code of Botanical Nomenclature to provide a Latin diagnosis or description for new taxa for most plant groups. This legislated requirement is considered a less onerous task for the specialist than would be perusing the literature in all the major scientific languages for information on newly described taxa. In addition, even partial facility in the Latin language opens a portal to a vast cultural and scientific literature. The Dictionary was originally compiled as a personal resource by P.M. Eckel, Missouri Botanical Garden, and is here shared with other taxonomists. The sections of the Dictionary are being added to the online database in reverse alphabetic order (Z to A) for good and sufficient reasons, including ease in cross-referencing. ... [Information of the supplier]