Yes, it is. Quoting the Wikipedia article you refer to:
"One common type of equalizer is the graphic equalizer which consists of a bank of sliders for boosting and cutting different bands"
That's exactly what you get with the iTunes equalizer. There are only ten bands, but it's still a graphic EQ.
If you're looking for something with more bands than the EQ built into iTunes, that's a different question. One possibility would Rogue Amoeba's Audio Hijack which can be used with industry-standard AudioUnit and VST plugins, of which there are at least a couple of EQ options.
Message was edited by: Dave Sawyer