smirch 
(smûrch)
(smûrch)tr.v. smirched, smirch·ing, smirch·es
1. To soil, stain, or dirty with or as if with a smearing agent: "their tough, hostile faces, smirched by the grime and rust" (Henry Roth).
2. To dishonor; defame.
n.
Something, such as a blot, smear, or stain, that smirches.
[Middle English smorchen.]