ad hominem\ad-HAH-muh-nem\
adjective
1 :
appealing to feelings or prejudices rather than intellect
2 :
marked by or being an attack on an opponent's character rather than by an answer to the contentions made
The governor's only response to the criticism of his new policy was to launch an ad hominem attack against those doing the criticizing.
"This democratization of the online media comment world results in both a lot of angry, nasty and downright insulting ad hominem attacks, followed quickly by ad hominem attacks by email commentators on each other that make for salty and entertaining, if not particularly edifying, reading." — From an editorial by Richard Hermann in the Daily Messenger (Canandaigua, New York), August 30, 2012