geology

noun

ge·​ol·​o·​gy jē-ˈä-lə-jē 

plural geologies

1

a

: a science that deals with the history of the earth and its life especially as recorded in rocks

b

: a study of the solid matter of a celestial body (such as the moon)

2

: geologic features

the geology of Arizona

3

: a treatise on geology

geologist

jē-ˈä-lə-jist 

noun

Examples of geology in a Sentence

learning about the geology of Hawaii

Recent Examples on the Web

But experts say Greenland’s harsh environment, limited infrastructure, and complex geology make mining those materials extraordinarily difficult, regardless of who controls the territory. —Kaif Shaikh, Interesting Engineering, 12 Jan. 2026

Envision, which began construction in 2025, will map the atmosphere and geology of Earth's closest neighbor, the fiery Venus. —Tereza Pultarova, Space.com, 12 Jan. 2026

The Grand Canyon floor is also a wonderful trip for geology buffs. —Stephanie Vermillion, Travel + Leisure, 11 Jan. 2026

Season One concludes with the Texas Tech geology graduate abandoning a well crew after tragedy strikes, only to achieve rapid success in his personal and work endeavors. —Michael M. Rosen, The Washington Examiner, 9 Jan. 2026

Word History

Etymology

New Latin geologia, from ge- + -logia -logy

First Known Use

1735, in the meaning defined at sense 1a

Rhymes for geology

• anthology
• apology
• astrology
• biology
• christology
• chronology
• conchology
• cosmology
• cryptology
• cytology
• doxology
• ecology

Kids Definition

geology

noun

ge·​ol·​o·​gy jē-ˈäl-ə-jē 

plural geologies

1

a

: a science that deals with the history of the earth and its life especially as recorded in rocks

b

: a study of the features of a heavenly body (as the moon)

2

: the geologic features (as mountains or plains) of an area

geologic

ˌjē-ə-ˈläj-ik

adjective

or geological

-i-kəl

geologically

-i-k(ə-)lē

adverb

geologist

jē-ˈäl-ə-jəst 

noun