What is the vowel associated with the letter “dalet” in the name “Aleph-Dalet-Nun-Yud”? I always assumed it was a “cholam” (see here for example) but someone who is (otherwise) careful in his pronunciation seems to make it a “kometz” or maybe a “patach”. Sourced answers vastly preferred.
There are two different names you may be referring to. In Genesis 19:2 it says:
thereby using a patach under the nun to denote "my masters."
However in Deuteronomy 3:24 it says:
thereby using a kamatz under the nun to denote "The Lord" [a name for God].
I note that there also exists that word with a chirik (Genesis 44:19) or tzeirei (I Kings 16:24) under the nun (meaning "my master" and "masters of" respectively) but I am not aware on any spelling with a cholom on the nun.
Note: in addition to showing the different vowels under the nun, these pesukim do show rather conclusively that the vowel on the dalet is always a cholom. I can't find any instance in tanach without the cholom on the dalet in the context of shem hashem.