The Collaborative International Dictionary of English v.0.48:

Distain \Dis*tain"\, v. t. [imp. & p. p. Distained; p. pr. &
   vb. n. Distaining.] [OE. desteinen, OF. desteindre to take
   away the color, F. d['e]teindre; pref. des- (L. dis-) + F.
   teindre to tinge, dye, L. tingere. See Tinge, and cf.
   Stain.]
   To tinge with a different color from the natural or proper
   one; to stain; to discolor; to sully; to tarnish; to defile;
   -- used chiefly in poetry. "Distained with dirt and blood."
   --Spenser.
   [1913 Webster]

         [She] hath . . . distained her honorable blood.
                                                  --Spenser.
   [1913 Webster]

         The worthiness of praise distains his worth. --Shak.
   [1913 Webster]