As a follow-up on Conservatism isn’t, I found it necessary to say that “liberalism” also isn’t applied to its meaning, but to two different things, depending on European or American cultural background.
As per definition, liberalism is “the belief in the importance of individual freedom”. This is of course the opposite of “totalitarianism”, and not the opposite of “conservatism” (whose opposite would be “progressivism”).
Now, in Europe, liberalism has taken on the meaning of a hard “economic liberalism”, meaning “the belief in the importance of freedom for companies only”. Capitalism, if you wish. In the USA, it has taken quite another meaning, some kind of “social liberalism”. This is a bit more difficult to express with a similar phrase like the above, it’s more like “Welfare is more important than freedom” (on the other side, the European version from above could be put as “Economy is more important than freedom”).
The main point about both these views is, that “liberalism” is not any more associated with individual freedom, but in one case with a freedom for business to override individual freedom (in order for economy to prosper), and in the other case with the freedom of the state to override individual freedom (in order to guarantee welfare).
Apparently, liberals (in the original sense) have noticed this shift of meaning, and can now be found as “libertarians”. Apart from widely-differing opinions on everything else, they can indeed be characterised by what was initially the definition of liberalism: “the belief in the importance of individual freedom”.