interpolate
verb (used with object)
to introduce (something additional or extraneous) between other things or parts; interject; interpose; intercalate.
Used to describe an ongoing action or continuous state that was happening at a specific time in the past.
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
But why did men who were interpolating bronze corslets freely introduce bronze so seldom, if at all, as the material of greaves?
From Homer and His Age by Andrew Lang