astronomical

adjective

as·​tro·​nom·​i·​cal ˌa-strə-ˈnä-mi-kəl 

variants or less commonly astronomic

ˌa-strə-ˈnä-mik 

1

: of or relating to astronomy

astronomical observations

2

: enormously or inconceivably large or great

astronomical numbers

an astronomical price

astronomically

ˌa-strə-ˈnä-mi-k(ə-)lē 

adverb

Synonyms of astronomical

• huge
• enormous
• vast
• tremendous
• gigantic
• massive
• giant
• colossal
• monumental
• immense
• mammoth
• bumper
• titanic
• mountainous
• cosmic
• planetary
• monstrous

Examples of astronomical in a Sentence

The cost of the office building was astronomical.

We got an astronomical telephone bill this month.

Recent Examples on the Web

Of course, removing yourself from the addictive algorithms that are driving astronomical user growth and ad revenues on other social platforms, does come with risk. —Lucy Maguire, Vogue, 5 Jan. 2026

Even though that group is expected to be the core foundation of what the defense is built around moving forward, that is an astronomical number to pay to the position. —Nick Harris, Fort Worth Star-Telegram, 5 Jan. 2026

The cosmic dipole anomaly has thus established itself as a major challenge to the standard cosmological model, even if the astronomical community has chosen to largely ignore it. —Subir Sarkar, Space.com, 5 Jan. 2026

Forecasters say that high astronomical tides Sunday and Monday morning will result in minor tidal overflow at some beaches. —Gary Robbins, San Diego Union-Tribune, 3 Jan. 2026

Word History

Etymology

Late Latin astronomicus "of or relating to astronomy" (borrowed from Greek astronomikós "of astronomy, skilled in astronomy," from astronomía astronomy + -ikos -ic entry 1) + -al entry 1

First Known Use

1551, in the meaning defined at sense 1

Phrases Containing astronomical

• astronomical unit

Rhymes for astronomical

• anatomical
• economical
• comical
• neuroanatomical
• uneconomical

Kids Definition

astronomical

adjective

as·​tro·​nom·​i·​cal ˌas-trə-ˈnäm-i-kəl 

variants also astronomic

-ˈnäm-ik 

1

: of or relating to astronomy

2

: extremely or unbelievably large

the cost was astronomical

astronomically

-ˈnäm-i-k(ə-)lē 

adverb