astronomical

astronomical — adjective

1. so high or so big that it is hard to believe — usually said of money, prices, de

1.adjectiveC1
Definition

so high or so big that it is hard to believe — usually said of money, prices, debts, or numbers far beyond what people normally see.

Example

The cost of rebuilding the bridge after the flood was astronomical.

subject is a cost / price noun

Xander's phone bill was astronomical after her trip to Iceland.

common collocation: astronomical bill

Common collocations
  • astronomical sum
  • astronomical fees
  • astronomical odds
  • astronomical debt
Synonyms
  • exorbitant

    specifically about prices that feel unfair

  • sky-high

    informal; usually about prices or rates

  • staggering

    stresses the shock more than the actual size

Antonyms
  • tiny

    neutral opposite for amounts

  • negligible

    formal; small enough to ignore

Grammar Patterns

astronomical + amount/cost/figure/sum

Usage Note

Subject or modified noun is almost always something countable in money, debt, fees, odds, or large numbers. Rarely used for physical size — say 'enormous' for a building or a person.

Common Mistakes

My new dog is astronomical.
My new dog is enormous.
'astronomical' describes amounts and prices, not the physical size of an object.

2. to do with the science that studies stars, planets, and other things far out in

2.adjectiveC1
Definition

to do with the science that studies stars, planets, and other things far out in space.

Example

Dr. Yara spent the night taking astronomical photographs of Jupiter from the rooftop.

before noun: astronomical photograph

The university has a small astronomical society that meets every Friday.

before noun: astronomical society

Common collocations
  • astronomical research
  • astronomical observation
  • astronomical society
  • astronomical discovery
Synonyms
  • celestial

    more about the sky and heavens themselves than the science

  • stellar

    specifically about stars

Usage Note

Almost always used before a noun (research, observation, society, photograph). Rarely used after a linking verb such as 'be'.

Common Mistakes

The lecture was astronomical.
The lecture was about astronomy.
use 'astronomical' before a noun, not as the main thing being described.

3. used to describe equipment — such as a telescope, camera, or pair of binoculars

3.adjectiveC2
Definition

used to describe equipment — such as a telescope, camera, or pair of binoculars — that is built specifically for observing or measuring stars and planets.

Example

Kofi saved for a year to buy a proper astronomical telescope for his garden.

before noun: astronomical telescope

The lab uses an astronomical camera that can take pictures of very faint stars.

before noun: astronomical camera

Common collocations
  • astronomical telescope
  • astronomical camera
  • astronomical binoculars
  • astronomical instruments
Synonyms
  • stargazing

    informal; usually before 'equipment' or 'gear'

Usage Note

Distinguish from sense 2: this sense names equipment built for the work (telescope, camera, binoculars, instruments), while sense 2 names the work itself (research, society, discovery).

Word family

Synonym discussion

Sense: adjective/1

All four words describe amounts that feel too big, but each highlights a different angle. 'Astronomical' suggests the figure is so far beyond ordinary that it feels almost unreal — fitting for national debts or lottery odds. 'Exorbitant' carries a moral judgement: the price is unreasonable or unfair, often used about rents and fees. 'Sky-high' is informal and visual, common in conversation about prices and interest rates rising fast. 'Staggering' focuses on the shock effect on the listener rather than the size itself, and pairs well with sums, losses, and statistics. So you might say 'an astronomical fine, an exorbitant rent, sky-high gas prices, a staggering loss' — same general territory, very different flavours.

astronomical ↗exorbitantsky-highstaggering

Common collocations

Nouns

Adverbs

  • truly astronomical
  • almost astronomical

Phrases

  • at astronomical prices
  • rise to astronomical levels

Etymology

GreekLatinOld FrenchEnglish

Built from the Greek word 'astron' (star) plus '-nomia' (the study or arrangement of something), which together gave Latin 'astronomia' and then English 'astronomy'. The adjective 'astronomical' first meant simply 'connected with the study of stars'. By the late 1800s, English speakers started using it as a hyperbole for any number that felt as big as the distances between stars, and that everyday sense is now the most common one.