Zeno (or Zenon, Greek: Ζήνων; 3rd and 2nd centuries BC) was a Greek physician.
He was one of the most eminent of the followers of Herophilus,[1] whom Galen calls "no ordinary man,"[2] and who is said by Diogenes Laërtius[3] to have been better able to think than to write. He lived probably at the end of the 3rd and beginning of the 2nd centuries BC, as he was a contemporary of Apollonius Empiricus, with whom he carried on a controversy concerning the meaning of certain marks (Greek: χαρακτῆρες) that are found at the end of some of the chapters of the third book of the Epidemics of Hippocrates.[4] He gave particular attention to the materia medica,[5] and is perhaps the physician whose medical formulae are quoted by Galen,[6] in which case he must have been a native of Laodicea. He is mentioned in several other passages by Galen, and also by Erotianus;[7] perhaps also by Pliny,[8] Caelius Aurelianus,[9] Alexander of Aphrodisias,[10] and Rufus of Ephesus,[11] but this is uncertain.