1.nounA single thickness of some material covering a surface.
"After the first coat of paint dried, he applied another layer."
2.nounA (usually) horizontal deposit; a stratum.
"I find seven-layer cake a bit too rich."
3.nounOne of the items in a hierarchy.
"mired in layers of deceit"
4.noun(by analogy to a stack of transparencies) one in a stack of (initially transparent) drawing surfaces that comprise an image; used to keep elements of an image separate so that they can be modified independently from one another.
5.verbTo cut or divide (something) into layers
6.verbTo arrange (something) in layers.
"Layer the ribbons on top of one another to make an attractive pattern."