Dioscorĭdes in Harpers Dictionary of Classical Antiquities
（Διοσκορίδης). A Greek physician and man of science. He flourished about the middle of the first century A.D., and was the author of a work De Materia Medica (Περὶ Ὕλης Ἰατρικῆς) in five books. For nearly 1700 years this book was the chief authority for students of botany and the science of healing. Two short essays on specifics against vegetable and animal poisons (Alexipharmaca and Theriaca) are appended to it as the sixth and seventh books; but these are probably from the hand of a later Dioscorides of Alexandria. A work on family medicine is also attributed to him, but is not genuine. The Materia Medica has been edited by Sprengel (1829-30).
Pedanius Dioscorides in Wikipedia
Pedanius Dioscorides (circa 40-90 AD) is the author of a 5-volume encyclopedia about herbal medicine and related medicinal substances, i.e. a pharmacopeia, that was widely read for well more than a thousand years, and is of great historical value today.
A native of Anazarbus, Cilicia, Asia Minor, Dioscorides was "a Greek physician, pharmacologist and botanist who practiced in Rome at the time of Nero. He was a surgeon with the army of the emperor, so he had the opportunity to travel extensively, seeking medicinal substances (plants and minerals) from all over the Roman and Greek world."
Dioscorides wrote a five-volume book in his native Greek, Περὶ ὕλης ἰατρικής, known in English by its Latin title De Materia Medica ("Regarding Medical Materials") that is a "precursor to all modern pharmacopeias". It remained in use until about CE 1600. Unlike many classical authors, his works were not "rediscovered" in the Renaissance, because his book never left circulation. In the medieval age, De Materia Medica was circulated in Latin, Greek, and Arabic. While being reproduced in manuscript form through the centuries, it was often supplemented with commentary on Dioscorides' work, with minor additions from Arabic and Indian sources. The most important Greek manuscripts survive today in Mount Athos monasteries. A number of illustrated manuscripts of the De Materia Medica survive. The most famous of these is the lavishly illustrated Vienna Dioscurides produced in Constantinople in 512/513 AD. Heavily illustrated Arabic copies survive from the 12th and 13th centuries.
De Materia Medica is the premiere historical source of information about the medicines used by the Greeks, Romans, and other cultures of antiquity. The work also records the Dacian and Thracian names for some plants, which otherwise would have been lost. The work presents about 600 plants in all, although the descriptions are sometimes obscurely phrased. "Numerous individuals from the Middle Ages on have struggled with the identity of the recondite kinds" and some of the botanical identifications remain insecure guesses by today's experts.