More naming questions

[Sarithus]

I'm still not sure, to be honest. I think I might be missing something crucial. Let me see if I understand: So someone would arrive at a place and give it a name in their own language based on whatever, let's go with looks for simplicity. They call the river that has a lot of curves in it, 'Sathir'. The whole word Sathir/parts of it mean 'Bend' or something? Take the name, 'Taylor' or 'Baker', I'm not entirely sure what people mean when they say it comes from being a Tailor or that that person was once a baker. Was someone literally called Tailor after their job once and it eventually got changed to Taylor?

Extra question: I have Cilen Tureste and Cilen Antar, Thel Usir, Thel Xantir. Roughly, as obviously I haven't gone into real detail, cilen = Hills and Thel = Mount/Hill. What would I call hills if I wasn't doing it based on a language and I wasn't using descriptive names? I get naming rivers if I wasn't doing it on a language because it's just a name usually, but with hills it's two words or more. Would I just say that this was the hill of Xantir (xantir meaning something) but instead of putting Thel before it I'd just call it Xantir?

I'm so lost.