Reconstruction of Gandalf's Westron name

"Gandalf" is Old Norse for "Staff Elf", and under Tolkien's 'Linguistic Mapping', Old Norse corresponds to the Dalish language, which is related to Westron, the language 'translated' as English in the books.

I'm willing to settle for the Westron name since we know basically nothing about Dalish, and little about the closely related Rohanese.

The name possibly still begins with a G, as Gandalf uses the G rune as his signature. There is not, as far as I know, a known Westron word for "staff", but "Nimir" is Adunaic for "elf". (Adunaic is the direct ancestor to Westron) "Vandil" is a neo-Quenya word for staff, but I'm not sure of the sound changes needed to make it fit in (or if it would even make sense historically as a loanword).

"Golf" in Noldorin meant "branch" and by extension "wand". It's possible, assuming the GOLOB root co-existed with the more modern OLOB root, that this word made its way into Adunaic and came to take on the meaning of "staff". Short "o" became "a" in loanwords to Adunaic (PM320), so it would have become "galf", plus any additional sound changes.

We know next to nothing about Westron. If we trust Lisa Star’s report from Tyalle Tyalliéva 17 about a Westron manuscript from Marquette, we have the following words:

• NDER- > Q nér, S dîr; Adunaic narû vs. Westron rama ‘man’
• AN- > Q anna, S ann; Adunaic *yô vs. Westron casto ‘gift’
• TAM- > Q tamo, S tân; Adunaic tamar vs. Westron dramar ‘smith’

This should serve to demonstrate that:

• many Westron words, especially day-to-day words like ‘staff’ do not descend from only from Adunaic, but also from the local substrate languages.
• Even those where one might assume an Adunaic influence like for dramar, the descent does not seem direct, because t > dr would be a very unusual sound change.

In other words: We can’t really say.