cosmology

noun

cos·​mol·​o·​gy käz-ˈmä-lə-jē 

plural cosmologies

1

a

: a branch of metaphysics that deals with the nature of the universe

b

: a theory or doctrine describing the natural order of the universe

2

: a branch of astronomy that deals with the origin, structure, and space-time relationships of the universe

also : a theory dealing with these matters

cosmological

ˌkäz-mə-ˈlä-ji-kəl 

adjective

cosmologically

ˌkäz-mə-ˈlä-ji-k(ə-)lē 

adverb

cosmologist

käz-ˈmä-lə-jist 

noun

Did you know?

Cosmology and Star Trek

Most religions and cultures include some kind of cosmology to explain the nature of the universe. In modern astronomy, the leading cosmology is still the Big Bang theory, which claims that the universe began with a huge explosion that sent matter and energy spreading out in all directions. One reason why fans watch Star Trek is for the various cosmologies depicted in the show, including different conceptions of space, time, and the meaning of life.

Examples of cosmology in a Sentence

Recent Examples on the Web

The European Space Agency’s Planck satellite mapped the CMB from 2009 to 2013, and cosmologists used that map to nail down the standard model of cosmology, also called LCDM. —Anil Ananthaswamy, Scientific American, 1 Apr. 2025

That can help explain some of the biggest unsolved questions in cosmology. —David Faris, Newsweek, 17 Mar. 2025

The party never stops Perhaps all this overwhelming negativity regarding the end of the Universe is what prompted Nobel laureate Roger Penrose in 2010 to propose a completely different mechanism for the long-term fate of the Universe, something dubbed conformal cyclic cosmology, or CCC. —Paul Sutter, Ars Technica, 14 Jan. 2025

This hints that our best theory of the universe's evolution, the standard model of cosmology, could be wrong. —Robert Lea, Space.com, 20 Mar. 2025

Word History

Etymology

New Latin cosmologia, from Greek kosmos — see cosmic + New Latin -logia -logy

First Known Use

circa 1656, in the meaning defined at sense 1a

Rhymes for cosmology

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

Kids Definition

cosmology

noun

cos·​mol·​o·​gy käz-ˈmäl-ə-jē 

plural cosmologies

: a branch of astronomy that deals with the beginning, structure, and space-time relationships of the universe

cosmologist

-jəst 

noun