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Av·i·cen·na

(ăv′ĭ-sĕnə) also Ibn Si·na (ĭb′ən sēnə) Full name Abu Ali al-Husain ibn Abdullah ibn Sina. 980-1037.

Persian physician and Neoplatonist philosopher noted for his Canon of Medicine, a standard medical textbook used in Europe until the 17th century.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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