interpolate

American  

[in-tur-puh-leyt] / ɪnˈtɜr pəˌleɪt /

verb (used with object)

interpolated, interpolating

1. to introduce (something additional or extraneous) between other things or parts; interject; interpose; intercalate.

2. Mathematics. to insert, estimate, or find an intermediate term in (a sequence).

3. to alter (a text) by the insertion of new matter, especially deceptively or without authorization.

4. to insert (new or spurious matter) in this manner.

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verb (used without object)

interpolated, interpolating

1. to make an interpolation.

interpolate British  

/ ɪnˈtɜːpəˌleɪt /

verb

1. to insert or introduce (a comment, passage, etc) into (a conversation, text, etc)

2. to falsify or alter (a text, manuscript, etc) by the later addition of (material, esp spurious or valueless passages)

3. (intr) to make additions, interruptions, or insertions

4. maths to estimate (a value of a function) between the values already known or determined Compare extrapolate

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Other Word Forms

• interpolable adjective
• interpolater noun
• interpolative adjective
• interpolatively adverb
• interpolator noun
• interpolatory adjective
• noninterpolating adjective
• noninterpolative adjective
• uninterpolated adjective
• uninterpolative adjective

Etymology

Origin of interpolate

First recorded in 1605–15; from Latin interpolātus, past participle of interpolāre “to make new, refurbish, touch up,” equivalent to inter- “between, among, together” + -polā- verb stem (akin to polīre “to polish”) + -tus past participle suffix; inter-, polish

Example Sentences

To get around that issue, the BEA said that it will average September and November numbers to interpolate the October missing data.

From The Wall Street Journal • Jan. 7, 2026

I have no idea, but when somebody wants to interpolate or whatever it’s called, I never object because I always learn something about the song that I hadn’t known or anticipated.

From Los Angeles Times • Nov. 11, 2024

Zhang said that one of the hallmarks of the study is the optimization process that helps the researchers interpolate the distribution and geometries of the two different polymer materials needed.

From Science Daily • Nov. 28, 2023

As Swain explained, “we don’t have thermometers covering every square inch of the Earth,” so scientific groups use computer models to interpolate between data points, generating what is called a reanalysis.

From Scientific American • Jul. 11, 2023

He was also told to interpolate the series with a 'blank', that is, to think of nothing at all.

From Clever Hans (The horse of Mr. Von Osten): A contribution to experimental animal and human psychology by Pfungst, Oskar