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per-

pref.

1. Thoroughly; completely; intensely: perfervid.

2. Containing an element in its highest oxidation state: perchloric acid.

3. Containing a large or the largest possible proportion of an element: peroxide.

4. Containing the peroxy group: peracid.

[Latin, from per, through; see per¹ in the Appendix of Indo-European roots.]

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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