smooth, refine, polish
If you interpolate words into a piece of writing, you insert those words into it; such altering of the text could falsify it.
When you extrapolate a conclusion from a set of data you make an educated guess about something unknown.
(mathematics) calculation of the value of a function outside the range of known values
a discourteous manner that ignores accepted social usage
a message (spoken or written) that is introduced or inserted
make (a surface) shine
perfected or made shiny and smooth
showing regard for others in manners, speech, behavior, etc.
not carefully reworked or perfected or made smooth by polishing
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