n. In histology, the process or result of staining.
n. In pharm., the addition of a flavoring or coloring agent to the ingredients of a prescription.
n. A preparation for dyeing : coloring matter in a state for use; that which imparts color.
Word Usage
"What stands out in my mind as a textbook case is X-tinction Agenda, which cycled through X-Men, New Mutants, and X-Factor, three issues each, with each issue a chapter in a linear progression."