Ductor

Duc"tor (?), n. [L., fr. ducere to lead.] 1. One who leads. [Obs.] Sir T. Browne.

2. (Mach.) A contrivance for removing superfluous ink or coloring matter from a roller. See Doctor, 4. Knight.

Ductor roller (Printing), the roller which conveys or supplies ink to another roller. Knight.