...because the estate tax has the effect of being a tax on dying.
Why do they call the lobbying for prevention of medical treatment for women, Pro-life?
Because we think elective abortions (almost all abortions are elective) are not medical treatment, but rather a barbaric practice in which one person is killed for the convenience of the other, and in most cases is harmful in the long-term to the survivor as well. I feel strongly about this, but I'm not upset by people who want to call me "anti-abortion", because I am.
Why can't they call the opposition party by their actual name?
Uh....what? Do you mean "the Democratic Party" as opposed to the "Democrat Party"? I think that one is better chalked up to colloquial speech, regardless of what the Wikipedia article says.
But like I said - being a lifelong Republican and conservative activist, I know exactly zero people who would be upset if you didn't say "death tax", "pro-life", or "Democrat Party" (or PPACA instead of ObamaCare).