Ooh. Today we have a Latin term- ad hominem
Ad hominem is an adjective that describes an argument that appeals to personal considerations. It is most commonly used to describe arguments that attack a person instead of their logic. For example- Adam Curry thinks Apple should add wireless capabilities to their iPods. Adam Curry is an idiot, therefore Apple should not add wireless to iPods. This argument is a logical fallacy because it is predicated on Adam is an idiot. It attacks him personally instead of his idea. Therefore it is an ad hominem argument.
Just for the record I don’t think Adam is an idiot and I certainly would like to wirelessly sync my iPod with my computer.
An historical note for the lexophiles. This definition of ad hominem is new. The old, more historically accurate definition describes an argument not designed to attack the opponent but to appeal to the listener’s emotions. For example if I was running for mayor I could argue, “This city needs more playgrounds for the poor, suffering, disabled orphan.” By describing the orphans as poor, suffering and disabled I am appealing to the emotions not to logic. This argument fits the historical definition of ad hominem arguments.
In my experience I have never heard or read ad hominem describe an argument that didn’t attack an opponent. So if you read it or hear it probably means someone is attacking an opponent personally instead of their argument.
In either case these types of arguments, though perhaps effective, are usually a big no-no in formal rhetoric or debate.
Since ad hominem is Latin it doesn’t have an etymology just a translation. Ad means “to” and hominem means “man”. Ad hominem literally means “to the man.”