Proto-Indo-European
The reconstructed ancestor of the Indo-European language family. Search any root to trace its descendants across Latin, Greek, Sanskrit, Germanic, and beyond.
2059 reconstructed roots · Browse all
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Every English word has a history. Pick one and trace it back thousands of years to its Proto-Indo-European root.
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Well-studied reconstructions with full articles. Each traces a single ancestral form across dozens of modern languages.
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About this reference
Proto-Indo-European (PIE) is the hypothetical common ancestor of the Indo-European languages, spoken roughly 4500–2500 BCE. This site catalogues reconstructed roots and maps their descendants forward through the daughter branches—from Sanskrit and Greek to Latin, Germanic, and Celtic.
Each root page traces how a single reconstructed form gave rise to words across dozens of modern languages, governed by regular sound laws first identified in the nineteenth century. The site is open-access and free to use.