interpolate Look up interpolate at Dictionary.com
1612 (implied in interpolation) "to alter or enlarge (a writing) by inserting new material," from L. interpolatus, pp. of interpolare "alter, freshen up, falsify," from inter- "up" + polare, related to polire "to smoothe, polish." Sense evolved in L. from "refurbish," to "alter appearance of," to "falsify (especially by adding new material)."