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di·a·pir

(dīə-pîr′)

A geological structure formed when a mass of material of high plasticity and low density, such as salt, gypsum, or magma, pushes upward into overlying strata.

[French, from Greek diapeirein, to push through : dia-, dia- + peirein, to pierce; see per-² in the Appendix of Indo-European roots.]

di′a·piric adj.

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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