[in.ter.line] vt [ME enterlinen, fr. ML interlineare, fr. L inter- + linea line] (15c): to insert between lines already written or printed -- in.ter.lin.e.a.tion n
[2]interline vt [ME, fr. inter- + linen to line] (15c): to provide (a garment) with an interlining [3]interline adj (1897): relating to, involving, or carried by two or more transportation lines