List of organisms named after famous people (born before 1800)

In biological nomenclature, organisms often receive scientific names that honor a person. A taxon (e.g. species or genus; plural: taxa) named in honor of another entity is an eponymous taxon, and names specifically honoring a person or persons are known as patronyms. Scientific names are generally formally published in peer-reviewed journal articles or larger monographs along with descriptions of the named taxa and ways to distinguish them from other taxa. Following rules of Latin grammar, species or subspecies names derived from a man's name often end in -i or -ii if named for an individual, and -orum if named for a group of men or mixed-sex group, such as a family. Similarly, those named for a woman often end in -ae, or -arum for two or more women.

This list is part of the List of organisms named after famous people, and includes organisms named after famous individuals born before 1 January 1800. It also includes ensembles in which at least one member was born before that date; but excludes companies, institutions, ethnic groups or nationalities, and populated places. It does not include organisms named for fictional entities, for biologists, paleontologists or other natural scientists, nor for associates or family members of researchers who were not otherwise notable (exceptions are made, however, for natural scientists who are much more famous for other aspects of their lives, such as, for example, writer Johann Wolfgang von Goethe).

Organisms named after famous people born later can be found in:
 * List of organisms named after famous people (born 1800–1899)
 * List of organisms named after famous people (born 1900–1949)
 * List of organisms named after famous people (born 1950–present)

The scientific names are given as originally described (their basionyms); subsequent research may have placed species in different genera, or rendered them taxonomic synonyms of previously described taxa. Some of these names may be unavailable in the zoological sense or illegitimate in the botanical sense due to senior homonyms already having the same name.