The name of a person may appear in the Scripture in more than one form. For example, both דוד and דויד have been used for the name of king David. Differences in spelling can be very significant, as they can be used to distinguish between different persons. For example, the small difference in spelling between ארתחששתא and ארתחסשתא is quite important, as it helps one distinguish between the king Artaxerxes of Ezr 4:7, 6:14 and the king Artaxerxes of Ezr 7:1, Ne 2:1, who reigned at a later time. Now the name of king Nebuchadnezzar has been associated with seven words with similar but different spelling: נבוכדנצור, נבכדנצר, נבוכדנצר, נבוכדנאצר, נבכדנאצר, נבוכדראצר, and נבוכדראצור. This article shows that all seven words refer to the same person. These words are in this sense equivalent.
As for textual variants, this article follows the Aleppo Codex. There are a few places in which the St. Petersburg Codex differs from the Aleppo Codex: in 2Ki 24:11 it has נבוכדנאצר instead of נבכדנאצר, at the end of Dan 3:3 it has נבוכדנצר instead of נבכדנצר, in Dan 3:14 it has נבכדנצר instead of נבוכדנצר, and in Dan 4:37 (4:34) it has נבוכדנצר instead of נבכדנצר. According to the Bomberg/Ginsburg Hebrew Old Testament, the aforementioned forms of the Aleppo Codex are supported by other manuscripts, while the St. Petersburg Codex variants might have some significant support only in Dan 3:3.
Equivalence of נבוכדנצר and נבוכדנצור: Note that Ezr 2:1 corresponds to Ne 7:6. The former has נבוכדנצור מלך בבל, while the latterנבוכדנצר מלך בבל. So it could be concluded that נבוכדנצור and נבוכדנצר denote the same person.
Equivalence of נבכדנצר, נבוכדנצר, and נבוכדנצור: In Dan 4:37 (4:34), the St. Petersburg Codex has נבוכדנצר, while other manuscripts have נבכדנצר. So following the Aleppo Codex, the form of Dan 4:37 (4:34) is נבכדנצר. Every other occurrence of Nebuchadnezzar's name in Dan 4 is written in the form נבוכדנצר (see Dan 4:1, 4, 18, 28, 31, 33, 34, which have the Hebrew verse numbers 3:31, 4:1,15,25,28,30,31). The king used for himself the name נבוכדנצר in Dan 4:1, 4, 18, 34 (Dan 3:31, 4:1, 15, 31), but נבכדנצר in Dan 4:37 (4:34). The shorter form might emphasize the fact that he had humbled himself before the Lord. Thus, in view of Dan 4, it can be concluded that נבכדנצר and נבוכדנצר denote the same person.
Equivalence of נבוכדנאצר, נבכדנצר, נבוכדנצר, and נבוכדנצור: In Ezra and Nehemiah, all references to the Babylonian king who conquered Jerusalem and took the people into exile use the name נבוכדנצר. The only exception is Ezr 2:1, where we find נבוכדנצור. Now Ezr 1:7, 5:14, 6:5 and 2Ch 36:7 speak on the same topic, so it could be concluded that נבוכדנצר מלך בבל in Ezr 5:12-14 and נבוכדנאצר מלך בבל in 2Ch 36:6-7 are the same person.
Equivalence of נבכדנאצר, נבוכדנאצר, נבכדנצר, נבוכדנצר, and נבוכדנצור: Jer 27:6 and Jer 28:14 are in the same context and have similar statements, the latter reinstating the former. Therefore, it must be that נבוכדנאצר מלך בבל in Jer 27:6 and נבכדנאצר מלך בבל in Jer 28:14 refer to the same person. The same conclusion can be reached by comparing the first part of Dan 1:1 with the first part of 2Ki 24:1: נבוכדנאצר מלך בבל in Dan 1:1 and נבכדנאצר מלך בבל in 2Ki 24:1 must be the same person.
Equivalence of נבוכדראצר, נבכדנאצר, נבוכדנאצר, נבכדנצר, נבוכדנצר, and נבוכדנצור: Jer 52:4 corresponds to 2Ki 25:1, so נבוכדראצר מלך בבל and נבכדנאצר מלך בבל must be the same. The same conclusion can be reached by examining 2Ki 25:8 and Jer 52:12, which mention two times when Nebuzaradan came to Jerusalem, once on the 7th of the 5th month, and once on the 10th of the same month. Once again, נבוכדראצר מלך בבל in Jer 52:12 and נבכדנאצר מלך בבל in 2Ki 25:8 must be the same.
Equivalence of נבוכדראצור, נבוכדראצר, נבכדנאצר, נבוכדנאצר, נבכדנצר, נבוכדנצר, and נבוכדנצור: Note that Jer 49:30 and Jer 49:28 are in the same context, so נבוכדראצר מלך בבל and נבוכדראצור מלך בבל must be the same.
The seven versions of Nebuchadnezzar's name are used as follows.
נבוכדנצר, נבכדנצר, and נבוכדנצור: Excepting Ezr 2:1, נבוכדנצר is the name used for Nebuchadnezzar in Ezra, Nehemiah, and Esther. This name is also commonly used in Daniel. It does not appear, however, in any other books of the Bible. The other forms of Nebuchadnezzar's name that appear in Daniel are נבכדנצר (only six times) and נבוכדנאצר (only once, in Dan 1:1). The other form that appears in Ezra is נבוכדנצור, which is found only once in the Bible, in the kethib of Ezr 2:1. This longer version of נבוכדנצר appears to add emphasis to Nebuchadnezzar. The form נבכדנצר appears only in Daniel; it could be seen as a shorter version of נבוכדנצר. When referring to himself, Nebuchadnezzar used נבוכדנצר (Dan 4:4 (4:1)) and נבכדנצר (Dan 4:37 (4:34)). It should be noted that נבכדנצר and נבוכדנצר are the only versions of Nebuchadnezzar's name that appear in Aramaic. Overall, it could be concluded that נבוכדנצר is the name by which Nebuchadnezzar was remembered by the Scripture authors who lived after him. נבכדנצר and נבוכדנצור are closely related versions of this name.
נבוכדראצר and נבוכדראצור: The form נבוכדראצר is the typical version of Nebuchadnezzar's name in Jeremiah and the only version found in Ezekiel. No other books of the Bible use this form. The form נבוכדראצור appears only once in once in the Bible, in the kethib of Jer 49:28. This longer version of נבוכדראצר appears to add emphasis to Nebuchadnezzar. The book of Jeremiah uses also the forms נבכדנאצר and נבוכדנאצר in Jer 27:1-29:3, and these are the only forms of Nebuchadnezzar's name that are used in Jer 27:1-29:3.
נבוכדנאצר and נבכדנאצר: These two forms appear in Kings, Chronicles, Jer 27:1-29:3, and Dan 1:1.
As can be seen above, there are three main versions of the name of Nebuchadnezzar, each having some other closely related forms that are obtained by adding or removing waw letters. The longer forms that have more waw letters appear to have more emphasis. As for the three main versions of the name, the simplest explanation appears to be that they correspond to Nebuchadnezzar's name in three different languages. According to the BDB lexicon, נבוכדראצר comes from Babylonian. However, Aramaic was more common in the Babylonian empire. Note that נבוכדנצר and נבכדנצר are the forms used in Aramaic. It follows that the remaining forms נבוכדנאצר and נבכדנאצר must describe the Hebrew version of Nebuchadnezzar's name. However, it appears that due to the Babylonian exile, these Hebrew forms were eventually replaced by the Aramaic version of the name. This would explain why the Aramaic version of the name appears also in the Hebrew text of Ezra and Daniel, as well as in Nehemiah and Esther. At this point, an interesting observation is that since the passages of Kings and Chronicles that mention Nebuchadnezzar use the Hebrew version of his name, these passages must have been written at least in part at an earlier date than Ezra, Nehemiah, and Esther.