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

This weekend, the June solstice on June 21, 2026, marks the Northern Hemisphere's longest day and the astronomical start of summer. —Jamie Carter, Forbes.com, 20 June 2026

In fact, many on Wall Street fear that Tesla’s notched that astronomical market cap less on hopes of wonders to come, and more on the possibility SpaceX will bid something close to what the carmaker’s selling for to clinch a colossal takeover. —Shawn Tully, Fortune, 20 June 2026

While astronomical seasons depend on how the Earth moves around the sun, meteorological seasons are defined by the weather. —ABC News, 19 June 2026

According to the Old Farmer’s Almanac, the solstice is considered the start of astronomical summer, even though meteorologists track the season change earlier. —Hali Smith, Idaho Statesman, 19 June 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