c. 1600, Latin, literally "to a man," from ad "to" (see ad-) + hominem, accusative of homo "man" (see homunculus). Hence, "to the interests and passions of the person." Originally an argument or appeal to the known preferences or principles of the person addressed, rather than to abstract truth or logic.
Aristotle (Topics, viii 11) remarks that it is sometimes necessary to refute the disputant rather than his position, and some medieval logicians taught that refutation was of two kinds, solutio recta and solutio ad hominem, the latter being imperfect or fallacious refutation. [Century Dictionary]
also hoochie-coochie, hootchy kootchy, "erotic suggestive women's dance" (involving a lot of hip-grinding), 1898, of obscure origin, usually associated, without evidence, with the Chicago world's fair of 1893 and belly-dancer Little Egypt (who might not even have been there), but the word itself is attested from 1890, as the stage name of minstrel singer "Hoochy-Coochy Rice," and the chorus of the popular minstrel song "The Ham-Fat Man" (by 1856; see ham (n.2)) contains the nonsense phrase "Hoochee, kouchee, kouchee."
To-day, however, in place of the danse du ventre or the coochie-coochie we have the loop-the-loop or the razzle-dazzle, which latter, while not exactly edifying at least do not serve to deprave public taste. ["The Redemption of 'Old Coney,'" in Broadway Magazine, April 1904]