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

• enormous
• immense
• oceanic

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

The data paints a stark picture: AI startups face astronomical odds of failure. —Moin Roberts-Islam, Forbes.com, 30 June 2025

As Billy explains to his team, the two acted as card counters who were ready to get back at the casino — or teams with astronomical budgets and star power. —Derek Scancarelli, EW.com, 27 June 2025

Expect shore excursions that complement the astronomical theme, such as a visit to Stonehenge in England, a historic site believed to have been constructed to align with the winter and summer solstices. —Chrissie McClatchie, Travel + Leisure, 25 June 2025

In New York City, astronomical twilight, when the sun is between 12 and 18 degrees below the horizon and the last of the daylight disappears, is between 9:47 and 10:37 p.m. on June 25. —Jesse Emspak, Space.com, 25 June 2025

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