The term macaca has a variety of meanings and connotations, ranging from innocuous to perjorative.
The word can be a reference to a type of monkey, specifically the macaques which are native to Asia and North Africa.
The word macaca is also a racial slur used among some European cultures in referring to African immigrants. The term is derogatory in nature, demeaning those groups, likening them to the macaques in appearance.
The term, obscure as it may have been in the USA, came to light in the 2006 senatorial race between incumbent Virginia Senator George Allen and his Democrat party opponent James Webb.
The incident occurred when Allen, on the stump in far Southwestern Virginia, brought attention to a person in the crowd manning a video camera. That person was S. R. Sidarth, an American of Indian descent, a student at the University of Virginia, and a Webb campaign worker. Sidarth was the only person of color in the crowd of about 100 persons present. He had been filming the Allen campaign for the opposition, a tactic which is common for both sides to participate in. The tactic apparently rankled Allen, who pointed Sidarth out in the crowd and referred to him as 'macaca, or whatever'.
Following the event efforts were made to deflect charges that Allen had used a racial slur against a man of color in an otherwise white crowd in an effort to humiliate and demean him. Allen said he had made the term up, having no knowledge of its racial overtones. He said it was a composite of Sidarth's haircut which Allen said resembled a
mohawk (Sidarth had a
mullet, not a mohawk), and
caca, a scatological term. Efforts to deflect the gaff found little traction and the incident probably was responsible for Allen losing the Senate seat.
Not only did it cost Allen his Senate seat, it cost him a potential bid for the 2008 Republican Presidential nomination. Allen had been viewed by many as a conservative leader for that spot. The incident, coupled with a few other peccadillos, seems to have fatally derailed any presidential aspirations Allen might have entertained.
Allen, who had formerly been a very popular governor in Virginia, at one time seemed invincible. This one incident proved to be his Achilles heel.
The term macaca first appeared in the 1600s, of Flemish origin. It is an approximation of the Bantu word for monkey in southern Gabon and the Congo. The term followed along with the colonials, in their occupation as well as upon their return to the European continent. By the early 1800s the word had become part of the lexicon, used as a racial label for blacks.
Sources:
http://www.washingtonpost.com/wp-dyn/content/article/2006/08/14/AR2006081400589.html
http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2006/08/20/EDG0SJ799L1.DTL
http://www.salon.com/news/feature/2006/08/16/allen/
http://mediamatters.org/items/200608170001