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

Now, researchers are trying to figure out what extreme astronomical event created the particle and sent it flying toward Earth. —Ashley Strickland, CNN, 15 Feb. 2025

Most astronomical observations remain tethered to photons—yet photons can easily be blocked. —Meghan Bartels, Scientific American, 12 Feb. 2025

Once they are considered repeat offenders, the tax bills soar to the astronomical levels teams like the Warriors and Milwaukee Bucks have battled in recent years and the Boston Celtics are about to start feeling. —Jason Lloyd, The Athletic, 12 Feb. 2025

That's because even hydrogen, by far the universe's most abundant element, emits only a faint glow that our astronomical instruments have struggled to observe between stars and galaxies. —Robert Lea, Space.com, 12 Feb. 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