Definition of ink :
1. A fluid, or a viscous material or preparation of various kinds ( commonly black or colored), used in writing or printing.
2. A pigment. See India ink, under India.
3. The step, or socket, in which the lower end of a millstone spindle runs.
4. To put ink upon; to supply with ink; to blacken, color, or daub with ink.
indelible, marking, rotogravure, copying, lithographic, waterproof, soluble, disappearing, Chinese, permanent, tannin, drawing, India, aniline, erasable, soy-based, safety, sympathetic, logwood, invisible
color (part of speech: noun)