interline

/ˌɪntərˈlaɪn/
verb
  1. To insert something between the lines of a text or document.
    • The scholar would interline translations of ancient poems in the margins.
    • The editor asked me to interline my corrections in the manuscript.
    • She used a pencil to interline notes between the printed paragraphs.
  2. To provide a lining between the outer fabric and the inner lining of a garment, for extra warmth or structure.
    • The tailor decided to interline the coat with a layer of wool for winter.
    • She learned how to interline a dress to give it a better shape.
    • To make the jacket sturdier, they interline it with a stiff canvas.