The American Heritage Dictionary of Indo-European Roots traces over 13,000 words, representing nearly 1,350 basic roots, to their origins in Proto-Indo-European, the prehistoric ancestor of English. The dictionary includes an introductory essay by Dr. Calvert Watkins, explaining how it is possible to reconstruct the words of an ancient and unwritten language and describing what scholars have discovered about Proto-Indo-European culture. Interspersed throughout the body of the dictionary are Language and Culture notes that provide more detailed information on particularly interesting roots and the vocabulary derived from them. The Dictionary of Indo-European Roots is an indispensable resource for anyone interested in the history of English and its place within the Indo-European language family.   Calvert Watkins is the Victor S. Thomas Professor of Linguistics and the Classics, Emeritus, at Harvard University, and Professor-in-Residence in the Department of Classics and the Program in Indo-European Studies at the University of California, Los Angeles. He specializes in Indo-European comparative linguistics, especially Latin, Greek, Celtic, Hittite, and comparative morphology and poetics. He wrote the “Appendix of Indo-European Roots” for the first edition of The American Heritage Dictionary and has revised it for the third, fourth, and fifth editions.