Carbonize \Car"bon*ize\, v. t. [imp. & p. p. {Carbonized}; p. pr. & vb. n. {Carbonizing}.] [Cf. F. carboniser.] 1. To convert (an animal or vegetable substance) into a residue of carbon by the action of fire or some corrosive agent; to char. 2. To impregnate or combine with carbon, as in making steel by cementation.