n. The act of discoloring, or the state of being discolored; alteration of color.n. That which is discolored; a discolored spot; a stain: as, spots and discolorations of the skin.n. Specifically In entomology, an indistinct, paler, or discolored part of a surface; that which is colorless or nearly so, as if faded out.n. Alteration of complexion or of the appearance of things: as, the discoloration of ideas.