noun an artificial oyster bed.
2. layer ·noun one who, or that which, lays.
3. layer ·noun a shoot or twig of a plant, not detached from the stock, laid under ground for growth or propagation.
4. layer ·noun 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.