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

Several of those stocks are falling this week amid a resurfacing of concerns over Silicon Valley giants’ astronomical spending on AI initiatives. —Liz Napolitano, CNBC, 14 Nov. 2025

In addition, the Sun and other, farther astronomical objects emit radiation that living things do not experience on Earth. —Christopher Carr, The Conversation, 13 Nov. 2025

The winter solstice is the start of astronomical winter, when Earth's northern hemisphere is pointed the farthest away from the sun due to its tilted axis. —Jalen Williams, Freep.com, 12 Nov. 2025

The astronomical start date of a season is based on the position of the sun in relation to Earth. —Haadiza Ogwude, Cincinnati Enquirer, 10 Nov. 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