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ge·ol·o·gy

(jē-ŏlə-jē)

n. pl. ge·ol·o·gies

1. The scientific study of the origin, history, and structure of the earth.

2. The structure of a specific region of the earth's crust.

3. A book on geology.

4. The scientific study of the origin, history, and structure of the solid matter of a celestial body.

[Medieval Latin geōlogia, study of earthly things : Greek geō-, geo- + Greek -logiā, -logy.]

ge′o·logic (jē′ə-lŏjĭk), ge′o·logi·cal adj.

ge′o·logi·cal·ly adv.

ge·olo·gist n.

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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