interpolation

noun

in·ter·po·la·tion | \ in-ˌtər-pə-ˈlā-shən

plural interpolations

Definition of interpolation

1a : an act of interpolating something or the state of being interpolated : the introduction or insertion of something spurious or foreign … versions disfigured by the frequent and substantial interpolation of freely invented matter …— Bernard Knox

b : something that is introduced or inserted : an insertion or addition How can such interpolations be identified, and what literary processes led to these additions?— Jan Nattier

2 : the process of calculating an approximate value based on values that are already known The age of tephras that were not directly dated was estimated by linear interpolation from the calibrated date.— Richard J. Payne and Jeffrey J. Blackford