The Collaborative International Dictionary of English v.0.48:
Marking \Mark"ing\, n.
The act of one who, or that which, marks; the mark or marks
made; arrangement or disposition of marks or coloring; as,
the marking of a bird's plumage.
Marking ink, indelible ink, because used in marking linen.
Marking nut (Bot.), the nut of the Semecarpus Anacardium,
an East Indian tree. The shell of the nut yields a
blackish resinous juice used for marking cotton cloth, and
an oil prepared from it is used for rheumatism.