1. (n.) One who, or that which, lays.

2. (n.) 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.

3. (n.) A shoot or twig of a plant, not detached from the stock, laid under ground for growth or propagation.

4. (n.) An artificial oyster bed.

Appleton layer F layer Heaviside-Kennelly layer Van Allen belt arrange in layers belt bookie chemosphere delaminate desquamate exfoliate flake ionosphere isothermal region laminate lay down lay up lower atmosphere outer atmosphere photosphere scale stratify stratosphere stratum substratosphere tropopause troposphere upper atmosphere