English Reference
noun

geology

n.
US /dʒiˈɑɫədʒi/ UK /dʒɪˈɒlədʒi/ ge·ol·o·gy UK spelling geologies

  1. 01 B2 Upper Intermediate Science

    the science that studies the Earth's history, its rocks, and how it was formed.

    the scientific discipline concerned with the physical structure and substance of the Earth, its history, and the processes that act on it.

    Simple

    She decided to study geology because she was fascinated by how mountains are formed.

    In context

    Modern geology relies heavily on plate tectonics to explain the distribution of fossils and the formation of mountain ranges across different continents.

    Usage

    Uncountable when referring to the academic field of study.

    earth science
  2. 02 C1 Advanced Technical Science

    the specific types of rocks and soil found in a particular place.

    the geological features or rock formations of a specific region or area.

    Simple

    The geology of this island is mostly volcanic rock and black sand.

    In context

    The local geology consists primarily of limestone, which has led to the formation of extensive cave systems throughout the valley.

    Usage

    Can be used as a countable noun when comparing different regions.

    rock formationterrain

That creates a challenge for scientists hoping to study chemical evidence connected to the Moon's ancient geology or possible biology.

ScienceDaily· 25 Aug 2026

In the first year of Bachillerato , biology will be combined with geology and environmental sciences.

The Local· 19 Aug 2026

From geo- + -logy, partly after Renaissance Latin geōlogia, from Ancient Greek γεω- (geō-, “earth”) + Latin -logia (“the study of”), from Ancient Greek -λογία (-logía).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin Ancient Greek -λογία
Level B2 · Upper Intermediate
Frequency Frequent
Updated