When people on this website throw that word around the way liberals abuse "racist" and "nazi," it ceases to have its full meaning. You may disagree with Newt Gingrich on several points, but he remains one of the giants of modern conservativism, and the left rightly despises him because of it.
Or, as Andrew Sullivan said:
Gingrich is definitionally what conservatism, properly speaking, opposes. Conservatism was born in the eighteenth century against the grand pronouncements of the French philosophes; it roots itself in practice not theory; it distrusts massive, profound reorganization of anything. In all of this, Gingrich is, in fact, conservatism’s nemesis: an autodidact megalomaniac, contemptuous of existing institutions, and bent on dragging an entire culture, country and, yes, civilization into a fantastic pocket of his own small mind.