Smudge

гъст дим

gǎst dim

(dense smoke, such as used for fumigation)

петно

petno

(a blemish; a smear)

зацапвам

zacapvam

(to soil or smear with dirt)

опетнявам

opetnjavam

(to soil or smear with dirt)

размазвам

razmazvam

(to obscure by blurring)