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

Those are the astronomical odds a Powerball ticket buyer will need to overcome to win the jackpot prize. — Siladitya Ray, Forbes.com, 30 July 2026

Beyond shedding light on the origin of super-puffy planets, the TOI-791 discovery also serves as a reminder that countless surprises are likely hiding in old and new astronomical datasets. — Chris Young july 30, Refractor, 30 July 2026

While aboard Salyut 6, those cosmonauts made astronomical observations and studied the effects of spaceflight on the human body. — Tariq Malik, Space.com, 29 July 2026

That’s been used in the past to argue why astronomical gains can continue on their trajectory and continue defying fundamentals or logic, such as during the dot-com bubble. — Jason Ma, Fortune, 25 July 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