Definition of "Smear" :

noun: an act that brings discredit to the person who does it

noun: a blemish made by dirt

noun: a thin tissue or blood sample spread on a glass slide and stained for cytologic examination and diagnosis under a microscope

noun: slanderous defamation

verb: charge falsely or with malicious intent; attack the good name and reputation of someone

verb: cover (a surface) by smearing (a substance) over it

"Smear the wall with paint."

verb: make a smudge on; soil by smudging

verb: stain by smearing or daubing with a dirty substance