I think the most common definition is the melding of populist economics (which are actually probably best described as left-wing) with strident right-wing/nationalist social policy (anti-civil rights, anti-immigrant, authoritarian, etc.). In a way, it's the theoretical polar opposite of a libertarian, which are left-wing on social policy but right-wing on economics.
I agree with most (probably all) of this, but it's interesting to note that I get called a "fascist" almost as much as, if not more than, anything else.
It's come to be the word du jour for "anything that's not me", I think. I say that to be funny more than any cogent analysis, but from an accuracy standpoint, it's not far off.
But even that definition does not go far enough. I think for it to be typically fascist, you have to have the extra element of the power merger between private wealth and government in a fashion that the government uses its authoritarian powers to enrich private enterprise at the expense of the public coffers. The result is corporate handouts funded by high government debt.
This last element is what differentiates fascist-populist economic policy from progressive-populist economic policy. Because while government spending usually decreases economic inequality by redistributing capital in the form of paying jobs for the people (a very socialist goal), a fascist government will do the same thing, except for the purposes of purchasing political support from both the economic elites and its lower-level supporters. All while the public's civil rights and right to dissent are stripped away, and the government coffers are bankrupt. Bankrupting the government coffers is actually a right-wing strategy, because they prefer a crippled government that has no power to fight the interests of entrenched wealth.
That's why you see Republican administrations actually running UP government deficits, and Democratic administrations decreasing it.
See, you were right on the mark, and then blew it at the end. The last eight years is exactly what you describe in the previous two paragraphs, and then go and try to pin it all on the "REPUBLICANS". Like clock work. Cutting back room deals with Big Pharma, guaranteeing them profits in order to support legislation that redistributes wealth is EXACTLY what you're talking about, and EXACTLY what Barack did as one of his first actions in office. I firmly and unequivocally believe that what many are calling the "PC movement" (I try not to, though I douse that, as I don't have a better name for it) is just as chilling to the right to peaceful expression of view points as any stereotypical "right-wing" measures.
Now, let me be clear: I'm not doing the exact same thing back at you, because it's NOT a "Democrat" thing. Bill Clinton didn't do this when he was in office. These things are not "left/right" things. In my opinion, they are intellectual failings, which we see on both sides of the aisle.