extrapolation

American  

[ik-strap-uh-ley-shuhn] / ɪkˌstræp əˈleɪ ʃən /

noun

1. an act or instance of inferring an unknown from something that is known.

2. Statistics, Mathematics. the act or process of estimating the value of a variable or function outside the tabulated or observed range.

---

extrapolation Cultural  

1. A mathematical procedure designed to enable one to estimate unknown values of a parameter from known values. A common method of extrapolation is to look at data on a curve, then extend the curve into regions for which there is no data. Extrapolation is often used to predict the future.

---

Etymology

Origin of extrapolation

First recorded in 1870–75; extrapolat(e) + -(t)ion

Explanation

An extrapolation is kind of like an educated guess or a hypothesis. When you make an extrapolation, you take facts and observations about a present or known situation and use them to make a prediction about what might eventually happen. Extrapolation comes from the word extra, meaning “outside,” and a shortened form of the word interpolation. Interpolation might sound like a made-up word, but it’s not. An interpolation is an insertion between two points. So an extrapolation is an insertion outside any existing points. If you know something about Monday and Tuesday, you might be able to make an extrapolation about Wednesday.

Example Sentences

Extrapolation from laboratory data shows that even after 1,400 years 5 percent of a hydra population kept in these conditions would still be alive.

From Slate • Oct. 6, 2016

Extrapolation would occur if we used our model to predict temperature when the values for chirps are less than 18.5 or greater than 44.

From Textbooks • Feb. 13, 2015

Extrapolation from such estimates produces huge aggregate savings.

From BusinessWeek • Feb. 4, 2010

Extrapolation enthusiasts would look at those numbers and assume Jackson would spend 2019 burrowing beneath the turf, but on Sunday all his production came through the air.

From Slate

Extrapolation of the statistics of double stars which are greatly disparate in mass suggests that almost all single stars like the Sun should have planetary companions.

From "Cosmos" by Carl Sagan

Related Words

• calculation
• estimate
• estimation
• forecast