interlining

Noun

 * 1) A cloth lining between the outer and inner layers of a garment.
 * 2) Correction or alteration by writing between the lines; interlineation.
 * 3) The scheduling of vehicles to operate more than one route, or the selling of tickets for a trip across multiple carriers
 * 1) The scheduling of vehicles to operate more than one route, or the selling of tickets for a trip across multiple carriers