Il·li-ni'tion, n.
(-nĭsh'ŭn), n. [Lat. illinire, i. q. illinere, to besmear; prefix il, for in, and linire, or linere, to smear.]
Sense 1. A smearing or rubbing in or on, as of an ointment, liniment, &c.
Sense 2. That which is smeared or rubbed on.
Sense 3. A thin crust of some extraneous substance formed on minerals. [Rare.]
It is sometimes disguised by a thin crust or illinition of black manganese. Kirwan.