approximation

approximation — noun

1. a figure or amount given as a near estimate instead of a precise one

1.nounC1
Definition

a figure or amount given as a near estimate instead of a precise one

Example

The repair bill is only an approximation until the parts arrive.

used before final numbers are known

By noon, the officer gave an approximation of the crowd size.

approximation of + amount

Common collocations
  • rough approximation
  • quick approximation
  • approximation of the cost
  • approximation of the total
  • an approximation of the answer
Synonyms
  • estimate

    the closest general word and often more neutral in tone

  • guess

    less careful and can suggest little evidence

  • calculation

    stresses working something out, often with numbers

  • ballpark figure

    informal and mainly used for a rough number

Antonyms

Grammar Patterns

an approximation of the cost

make an approximation

a rough approximation

Usage Note

Often used for numbers, totals, time, distance, or cost when the speaker cannot yet give a final figure. Distinguish from sense 2, which describes a thing that resembles something else rather than a numerical estimate.

Common Mistakes

The cost is approximation 300 dollars.
The cost is approximately 300 dollars.
approximation is a noun, so it cannot directly replace the adverb approximately before a number.

2. something close to another thing in form or effect, but not fully the same

2.nounC1
Definition

something close to another thing in form or effect, but not fully the same

Example

The toy castle was a cheap approximation of the real building.

approximation of + original

Her paper mask was only an approximation of her grandfather's face.

Common collocations
  • close approximation to reality
  • poor approximation of the original
  • cheap approximation
  • visual approximation
  • approximation to the real thing
Synonyms
  • version

    broad and neutral, but not always close in detail

  • likeness

    often used when something looks like a person or object

  • imitation

    can suggest a copy and sometimes a less valuable one

  • model

    often refers to a physical or visual representation

Antonyms
  • original

    the real thing that the approximation is based on

  • exact copy

    matches the original much more fully

Grammar Patterns

an approximation of something

a close approximation to something

an approximation to the real thing

Usage Note

Usually followed by of or to when one object, picture, sound, or effect is compared with a real thing or a model. Distinguish from sense 1, which is mainly about rough numbers or amounts.

Common Mistakes

The model is an approximation for the old bridge.
The model is an approximation of the old bridge.
this sense usually links the similar thing to the original with of or to, not for.

Word family

Synonym discussion

Sense: noun/1

For sense 1, approximation suggests a number that is close enough for the moment, but not fully exact. Estimate is the broadest near-synonym and is often the normal choice in business, planning, or repair costs. Guess is weaker because it may be based on very little thought or evidence. Calculation stresses working something out with numbers, so it can be exact or rough depending on the method. Ballpark figure is informal and usually means a quick rough number. A mechanic may give an approximation before opening the engine, while an accountant later provides a careful estimate or calculation.

approximation ↗estimate ↗guess ↗calculation ↗ballpark figure

Common collocations

Phrases

  • a close approximation

Prepositions

Etymology

LatinEnglish

Approximation was formed in English from approximate and the noun ending -ion. Approximate comes from Latin approximare, meaning to come near. That idea of being near without fully reaching something still explains the modern word, whether it refers to a number or to something that only partly matches the real thing.