What does "liner" mean?

Liner: A vessel belonging to a regular line of packets; also, a line-of- battle ship; a ship of the line.

Additional senses

  1. 2.(Mach.) A thin piece placed between two parts to hold or adjust them, fill a space, etc., ; a shim.
  2. 3.(Steam Engine) 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.
  3. 4.A slab on which small pieces of marble, tile, etc., are fastened for grinding.
  4. 5.(Baseball) A ball which, when struck, flies through the air in a nearly straight line not far from the ground.

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