I asked this before on "askreddit", but i hope i would get here some more quality answers. Thank you
Edit: why and when did the meanings start to differ?
If you're talking about contemporary meanings you'd probably be better off asking at /r/asksocialscience. If you're looking for an historical account of its meaning in a specific time and place, please make that clear in your question description to help people provide a better answer.
Thanks.