What does "interpolation" mean?

Interpolation: That which is introduced or inserted, especially something foreign or spurious. Bentley wrote a letter . . . . upon the scriptural glosses in our present copies of Hesychius, which he considered interpolations from a later hand. De Quincey.

Additional senses

  1. 2.(Math.) The method or operation of finding from a few given terms of a series, as of numbers or observations, other intermediate terms in conformity with the law of the series.

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