Definitions of isms
How do we define the "left" and liberalism? How do we define the "right" and conservativism?
My theory, which is mine:
The only political ism that has a consistent definition across historical periods is "conservatism". That definition is: "maintaining the status quo of power."
That's it. What kind of philosophy or policies fall under conservatism will vary, depending on what groups have the most power in a particular society. In mid-19th century Europe, conservatives were on the side of the aristocrats; in modern America, they're on the side of large corporations.
This IMHO is why "classical liberalism" (of the 19thC) looks like modern conservatism: the bourgeois corporations served by that philosophy were not the top of the heap in the 19thC, but they are now. Philosophies follow interest groups, and it's the position of the group in the power structure that's the defining variable.
It's particularly confusing because everyone naturally tends to become conservative when they come into power -- "I support the status quo when it's *me*."
Fascism is more a pathology of authoritarianism than it is "conservative", but, as Orwell says, "rich men all over the world tend to sympathise with Fascism" -- and anything rich men sympathise with is pretty sure to be conservative by definition, because they have a lot of power.
So I'd say both: across cultures, "conservatism" means "protects the power of the powerful", and anything favored by most of the powerful is part of the local definition of "conservative".
In the English-speaking world, at least, we can even use the word "conservative" to track hierarchical status. So the fact that American conservatives are currently opposed to government regulation of business implies that business (or certain businesses) are more powerful than the government -- as is shown by the fact that they pay better.