n. pl. pe·riph·er·ies
1. A line that forms the boundary of an area; a perimeter.
2. The outside surface of an object.
3. The area along a boundary; the margin. See Synonyms at circumference.
4. An area of secondary status or lesser importance: works that have been relegated to the periphery of literary studies.
[Middle English periferie, from Medieval Latin periferia, from Late Latin peripherīa, from Greek periphereia, from peripherēs, carrying around : peri-, peri- + pherein, to carry; see bher-1 in the Appendix of Indo-European roots.]
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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:
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.