There are a number of important words and expressions, the meanings of which are very different, if not the complete opposite, of what they are generally assumed to be, so I thought I'd start a list of examples which spring to mind, and invite others to comment on them and/or add their own examples. I'm sure there must be many more examples for others to contribute. I'll add more of my own, as they occur to me.
Since I also speak German (as a second language), I'm happy to receive examples and comments in that language too.
RACISM: meaning, if you are white, a lack of contempt for one's own race. If you do not deny and despise your own white race, you must necessarily hate other races, especially black people. It is a way of equating any form of white racial identity and perfectly natural "racial prejudice" with evil (see BLOG in which I explain what I see as the power-political purpose of this and the following two examples of Orwellian newspeak).
DIVERSITY: meaning the melting pot of post-racial multicultural society which is actually destroys genuine human diversity (as it gradually dissolves and disappears into it), while undermining social cohesion and solidarity.
CELEBRATING DIVERSITY: meaning, if you are an ethnic European, i.e. white, to celebrate one's own ethnic displacement (white flight), replacement (whites have already been reduced to an ethnic minority in large swathes of major western cities) and ultimate demise. It is an expression of white racial self-denial, self-contempt and self-hatred.
LOVE CHILD: meaning a child conceived in an irresponsible, loveless union, which strikes me, not just as a LIE, but also as an insult to children conceived in responsible, loving relationships, whether inside or outside of marriage. I don't believe that the children of irresponsible, loveless unions should be demonised in any way, but neither should they be made out to be something they are not.