What does "layer" mean?

Layer: Etym: [Prob. a corruption of lair.] That which is laid; a stratum; a bed; one thickness, course, or fold laid over another; as, a layer of clay or of sand in the earth; a layer of bricks, or of plaster; the layers of an onion.

Additional senses

  1. 2.A shoot or twig of a plant, not detached from the stock, laid under ground for growth or propagation.
  2. 3.An artificial oyster bed.

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