system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does the word 'liberal' refer to the left in the US?

I assume it is because of the lack of a significant 'socialist' movement. In much of Europe, for example, liberals are considered centrist or even fiscal conservatives. Why is this not the case in the US? It confuses me.
gpt
The word liberal originally meant something like "people should have liberty." That meant stuff like elected government, rule of law, that kind of stuff. No one is really against that anymore so anyone can call them selves "liberals" by this old meaning. 

In the 20th century, one group of liberals became important in the US and a different one in Europe.  They both came out of the old meaning of liberal so they both called themselves liberal. 

In the US the thinking was something like, "To give people more liberty the government needs to help them out when they are down."

In Europe it was something like, "To give people more liberty the government needs to get out of the way."

Both are still about liberty but how to get it was very different.

An important note: Conservative's aren't against liberty. Of course not, By the old definition, conservatives are also liberals.  The opposite of a conservative isn't a liberal by that meaning, it's a progressive.