The ''clavis sanationis'' was written in the thirteenth century by Simon of Genoa, a physician to pope Nicolas IV. It is a multilingual dictionary that covers medical terminology in Latin, Greek and Arabic language. It uses, and often quotes, a number of valuable sources which are otherwise lost today.
 
The ''clavis sanationis'' was written in the thirteenth century by Simon of Genoa, a physician to pope Nicolas IV. It is a multilingual dictionary that covers medical terminology in Latin, Greek and Arabic language. It uses, and often quotes, a number of valuable sources which are otherwise lost today.
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Most entries would have the following structure: “The disease/plant v is called w in Arabic and x in Greek. According to source y it is defined by z”. In several cases, source y would have been lost in the course of the centuries.  
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Most entries would have the following structure: "The disease/plant v is called w in Arabic and x in Greek. According to source y it is defined by z". In several cases, source y was lost in the course of the centuries.