Firstly, Greek and Latin are very different languages and a name can't just be Latin/Greek - it has to originate from one or the other.
Secondly, that is not what Nora means. That meaning is a garbled version of two possible sources for the name - Honora, meaning 'honour', and Eleanor, which as a version of Helen is sometimes given as meaning 'light'. It doesn't. It possibly means 'torch', and there are another couple of possible meanings. It is by no means certain that Eleanor comes from Helen, so that meaning for Nora is even more doubtful.
When you look at the hard evidence, the resemblance between Nora and Nor / Nur is clearly a co-incidence.