I’ve never heard the terms fiscal conservative used as the opposite of “supply-sider”. And using liberal in the old definition is just a confusing term to use.
I am a lower taxes, supply-sider myself.
According to wikipedia, you’re right about fiscal conservativism and I’m right about economic liberalism.
According to wikipedia, economic liberalism is strongly associated, among other things, with “liberal conservatism” and with “conservative liberalism.”
As to what distinguishes these two things, gosh, I can only infer that Rudy Guiliani is a “conservative liberal,” whereas I think it is fair to say that most American conservatives are “liberal conservatives” (and only a few are “populist conservatives”).
According to the discussion, and I think this is reasoned, there has been an increasing amalgamation of most (classical) conservatives and (classical) liberals, as conservatives have come to embrace personal autonomy and freedom, and liberals have embraced the a role for tradition, the family and the church, and both have embraced a free-market economy.