ex·​trap·​o·​late | \ik-ˈstra-pə-ˌlāt \
extrapolated; extrapolating

Definition of extrapolate 

transitive verb

1a : to predict by projecting past experience or known data extrapolate public sentiment on one issue from known public reaction on others

b : to project, extend, or expand (known data or experience) into an area not known or experienced so as to arrive at a usually conjectural knowledge of the unknown area extrapolates present trends to construct an image of the future

2 : to infer (values of a variable in an unobserved interval) from values within an already observed interval

intransitive verb

: to perform the act or process of extrapolating

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Other Words from extrapolate

extrapolation \ik-​ˌstra-​pə-​ˈlā-​shən \ noun
extrapolative \ik-​ˈstra-​pə-​ˌlā-​tiv \ adjective
extrapolator \ik-​ˈstra-​pə-​ˌlā-​tər \ noun

The Many Uses of Extrapolate

Scientists worry about the greenhouse effect because they have extrapolated the rate of carbon-dioxide buildup and predicted that its effect on the atmosphere will become increasingly severe. On the basis of their extrapolations, they have urged governments and businesses to limit factory and automobile emissions. Notice that it's acceptable to speak of extrapolating existing data (to produce new data), extrapolating from existing data (to produce new data), or extrapolating new data (from existing data)—in other words, it isn't easy to use this word wrong.

Examples of extrapolate in a Sentence

We can extrapolate the number of new students entering next year by looking at how many entered in previous years. With such a small study it is impossible to extrapolate accurately.

Recent Examples on the Web

From that base of survey data, the researchers extrapolated to the whole island and came up with a range of excess deaths. Washington Post, "The Health 202: Medicaid expansion in red states is likely to come via voters in November," 4 June 2018 The Gilead writers aren’t just extrapolating from Atwood’s ideas or referencing the mistreatment of women throughout human history. Joanna Weiss, BostonGlobe.com, "In a #MeToo world, the dark allure of ‘The Handmaid’s Tale’," 27 May 2018 And Voyles points out that the study is limited geographically and cannot be used to extrapolate a broad truth about a global problem. The Washington Post, NOLA.com, "Some endangered frogs may be leaping back from extinction," 17 May 2018 In New York, counties with the largest Lyme burden investigate only 20% of positive laboratory reports and then extrapolate to estimate the full number of cases. Jo Craven Mcginty, WSJ, "Lyme Disease: An Even Bigger Threat Than You Think," 22 June 2018 Is extrapolating from a few hours' worth of press briefings and demos to a cohesive analysis of the prospects of gaming at large isn't a foolproof venture? Julie Muncy, WIRED, "January Is the New November, and Other Surprising E3 Trends," 15 June 2018 Interpreting ancient predictive patterns to fit today and extrapolating from that to what will happen tomorrow is an ancient practice. Rabbi David Wolpe, Time, "Why We Shouldn't Be So Sure of Our Predictions About the Future," 20 Apr. 2018 This is also a sort-of reference to the Bible, though more to an old, racist theological concept extrapolated by some Christians from the text, used to justify slavery and discrimination against dark-skinned people. Alissa Wilkinson, Vox, "What two fictional Gileads can teach us about America in 2018," 12 July 2018 His office will review a 3 percent sampling of petitions and then extrapolate the results to come up with a projected total of valid signatures. Lori Weisberg, sandiegouniontribune.com, "Will convention center initiative qualify for ballot? Signatures are turned in," 9 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'extrapolate.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of extrapolate

1874, in the meaning defined at transitive sense 2

History and Etymology for extrapolate

Latin extra outside + English -polate (as in interpolate) — more at extra-

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Statistics for extrapolate

Last Updated

3 Nov 2018

Look-up Popularity

Time Traveler for extrapolate

The first known use of extrapolate was in 1874

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More Definitions for extrapolate



English Language Learners Definition of extrapolate

: to form an opinion or to make an estimate about something from known facts

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Comments on extrapolate

What made you want to look up extrapolate? Please tell us where you read or heard it (including the quote, if possible).


to move with a clumsy heavy tread

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