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

• Brobdingnagian
• bumper
• colossal
• cosmic
• cosmical
• cyclopean
• elephantine
• enormous
• galactic
• gargantuan
• giant
• gigantesque
• gigantic
• grand
• herculean
• heroic
• heroical
• Himalayan
• huge
• humongous
• humungous
• immense
• jumbo
• king-size
• king-sized
• leviathan
• mammoth
• massive
• mega
• mighty
• monster
• monstrous
• monumental
• mountainous
• oceanic
• pharaonic
• planetary
• prodigious
• super
• super-duper
• supersize
• supersized
• titanic
• tremendous
• vast
• vasty
• walloping
• whacking
• whopping

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

Upcoming celestial events This year, the December full moon occurs one week before the winter solstice, an astronomical event caused by the Earth’s tilt, that marks the Northern Hemisphere’s longest night and shortest day and vice versa for the Southern Hemisphere. —Taylor Nicioli, CNN, 14 Dec. 2024

Here's a list of the 2025 astronomical events to put on your viewing calendar this year: Meteor showers that will be visible in 2025: Meteor showers are caused by debris entering the Earth's atmosphere at 35 kilometers per second, according to NASA. —Alex Groth, Journal Sentinel, 13 Dec. 2024

Just a few miles from ALMA is the University of Tokyo Atacama Observatory, the world’s highest astronomical observatory at 5,640 meters atop Cerro Chajnantor in Chile, which opened in May. —Jamie Carter, Forbes, 13 Dec. 2024

The organization keeps track of meteor sightings and your report can help alert and inform scientists about important astronomical events. —John Tufts, The Indianapolis Star, 10 Dec. 2024

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

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