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

Regardless of whether one studies cosmology, particle physics, medicine or chemical processes, one is always dealing with variable systems and thus with differential equations. —Manon Bischoff, Scientific American, 12 May 2026

This puzzle is widely considered to be the biggest mystery in modern cosmology. —Robert Lea, Space.com, 12 May 2026

The 37-year-old artist has gained international attention for her darkly humorous videos and installations that explore Indigenous identity and cosmologies, ecology, futurism, and the line between history and myth. —Harrison Jacobs, ARTnews.com, 29 Apr. 2026

And that those speeds exceed what a dark matter-rich cosmology operating under Einstein’s general theory of relativity would predict, where cluster collision speeds more typically cap out around 4000 km/s or so. —Big Think, 29 Apr. 2026

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