verb.
To tarnish, especially someone's reputation; to debase.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
verb.
smear so as to make dirty or stained
verb.
charge falsely or with malicious intent; attack the good name and reputation of someone
Word Usage
"GARY TUCHMAN, CNN NATIONAL CORRESPONDENT (voice-over): A warning from Michael Jackson's attorney to those who want to -- quote -- "besmirch" the king of pop's reputation."