The scientific study of the origin, history, and structure of the earth.
The structure of a specific region of the earth's crust.
A book on geology.
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.