noun one who lines, as, a liner of shoes.
2. liner ·noun a slab on which small pieces of marble, tile, ·etc., are fastened for grinding.
3. liner ·noun a thin piece placed between two parts to hold or adjust them, fill a space, ·etc.; a shim.
4. liner ·noun a vessel belonging to a regular line of packets; also, a line-of-battle ship; a ship of the line.
5. liner ·noun a ball which, when struck, flies through the air in a nearly straight line not far from the ground.
6. liner ·noun a lining within the cylinder, in which the piston works and between which and the outer shell of the cylinder a space is left to form a steam jacket.