interpolate
Pronunciation: /ɪnˈtəːpəleɪt/
verb
- 1insert (something of a different nature) into something else: illustrations were interpolated in the text
- insert (words) in a book or other text, especially in order to give a false impression as to its date.
- alter or enlarge (a text) by insertion of new material.
- Mathematics insert (an intermediate value or term) into a series by estimating or calculating it from surrounding known values.


Origin:
early 17th century: from Latin interpolat- 'refurbished, altered', from the verb interpolare, from inter- 'between' + -polare (related to polire 'to polish')