The definition of interlining is the material between the fabric on the outside of a piece of clothing and the regular lining.
An example of interlining is wool sewn between the nylon and fleece of a winter jacket.
- an inner lining put between the outer material and the ordinary lining of a garment
- any fabric used to make such an inner lining
An extra lining between the outer fabric and regular lining of a garment.
inter- + lining