Meaning : A message (spoken or written) that is introduced or inserted.
Example :
With the help of his friend's interpolations his story was eventually told.
With many insertions in the margins.
Synonyms : insertion
Meaning : (mathematics) calculation of the value of a function between the values already known.
Meaning : The action of interjecting or interposing an action or remark that interrupts.
Synonyms : interjection, interpellation, interposition