noun

interpolation

in-tur-puh-LAY-shun/ɪnˌtɜːrpəˈleɪʃn/

The insertion of something between existing elements.

The interpolation of the third tile fills the gap in the numbered sequence.

A numbered tile marked 3 is being inserted into the open space between 2 and 4 in an otherwise continuous row of tiles numbered 1, 2, 4, 5.

Etymology

interLatinamong, between

+polLatinto polish, freshen up

+ationLatinact or process

The polishing element, combined with inter-, formed a verb meaning “refurbish,” then “alter” and “falsify,” especially by adding material to writing. Interpolation retains that insertion aspect without necessarily implying falsification.

In context

YourCalvinist (Podcast) with Keith Foskey18:13

This statement is actually probably an interpolation that wasn't even written by Ignatius.

What do LANDMARK BAPTISTS believe? ***Bow Tie Dialogue***

More examples

A later interpolation adds two lines to the poem.
Linear interpolation estimates the temperature between two recorded measurements.
Several interpolations appear in a different handwriting.

Forms

interpolation · interpolations

interpolate verb — Insert something between existing elements.

Similar words

insertion: A broader term for putting something into something else.
addition: Something added, not necessarily placed between existing elements.