What does "underlay" mean?

Underlay: To raise or support by something laid under; as, to underlay a cut, plate, or the like, for printing. See Underlay, n., 2.

Additional senses

  1. 2.To put a tap on (a shoe). [Prov. Eng.]
  2. 3.To incline from the vertical; to hade; -- said of a vein, fault, or lode.
  3. 4.(Mining) The inclination of a vein, fault, or lode from the vertical; a hade; -- called also underlie.
  4. 5.(Print.) A thickness of paper, pasteboard, or the like, placed under a cut, or stereotype plate, or under type, in the from, to bring it, or any part of it, to the proper height; also, something placed back of a part of the tympan, so as to secure the right impression.

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