Mizrahi Hebrew, or Eastern Hebrew, refers to any of the pronunciation systems for Biblical Hebrew used liturgically by Mizrahi Jews: Jews from Arab countries or east of them and with a background of Arabic, Persian or other languages of Asia. As such, Mizrahi Hebrew is actually a blanket term for many dialects.
Sephardi Hebrew is not considered one of these, even if it has been spoken in the Middle East and North Africa. The Sephardim were expellees from Spain and settled among the Mizrahim, but in countries such as Syria and Morocco, there was a fairly high degree of convergence between the Sephardi and the local pronunciations of Hebrew. Yemenite Hebrew is also considered quite separate, as it has a wholly different system for the pronunciation of vowels.
The same terms are sometimes used for the pronunciation of Modern Hebrew by Jews of Mizrahi origins. It is generally a compromise between Modern Standard Hebrew and the traditional liturgical pronunciation as described in this article. A common form of such compromise is the use of [ħ] and [ʕ] for ח and ע, respectively, with most or all other sounds pronounced as in Standard Israeli Hebrew.
The following features are generally found in the pronunciation of Jews from Arabic-speaking countries, and the variations tend to follow the Arabic dialect of the country in question.
The pronunciation of Mizrahi Jews from non-Arab countries differs in some respects. For example, among Persian Jews, distinctively Arabic sounds such as ح [ħ] and ط [tˤ] do not occur, and Kamatz gadol is pronounced [ɒ], like the long a in Persian.
In Talmudic times, it was noted that the Galilean (and maybe Syrian) pronunciation of Hebrew and Aramaic differed from those of both Judaea and Babylonia, principally by the loss of distinct sounds for the guttural letters he, ḥet and ʿayin. That feature is still found in Samaritan Hebrew.
After the Arab conquest of Palestine and Mesopotamia, much work was done by the Masoretes in standardising and refining the pronunciation of Biblical Hebrew, under the influence of the Arabic grammarians of the time. That included establishing the pronunciation of the guttural letters by reference to their Arabic equivalents. Three distinct notations for the vowels were devised: the Palestinian, the Babylonian and the Tiberian, the last of which eventually superseded the others.
The distinctive Babylonian pronunciation of Geonic times is still preserved by Yemenite Jews, but they do not retain the Babylonian notation. In Iraq, it appears to have been superseded by the Palestinian pronunciation (similar to today's Sephardi Hebrew) in or around the 11th century, when the Tiberian notation was adopted: both Saadia Gaon and Jacob Qirqisani report that in their time the Palestinian pronunciation had come to be regarded as standard. Nevertheless, in their reading of unvocalised texts such as the Mishnah, Baghdadi Jews preserve certain peculiarities of the old Babylonian pronunciation, particularly with their choices between dagesh and rafe and between silent and vocal sheva.
The process of assimilation to Arabic went the furthest with the Babylonian Jews. For example, in Classical Arabic and in some spoken dialects including Mesopotamian Arabic, there is no phonemic distinction between a and e, but a phonetic difference is made by the presence of an adjacent emphatic or guttural consonant. Accordingly, the Babylonian notation does not distinguish between patach (in other pronunciations [a]), segol (in other pronunciations [e] or [ɛ]) and sheva na', and the three vowels are still pronounced alike (as [æ]) bu Yemenite Jews. In Levantine Arabic, by contrast, there are distinct "a" and "e" sounds, and both vowels are distinguished in both the Palestinian and the Tiberian notations.[d]
After the expulsion of the Sephardi Jews from Spain in 1492, the exiles took the leading position in most Arab and Ottoman countries, and the local pronunciation of Hebrew assimilated to Sephardi Hebrew in many respects, particularly for pronouncing the vowels. Today's Iraqi Jews distinguish between patach (/a/) and segol (/e/) in the same way as most other Sephardi and Mizrahi Jews. However, distinct sounds for the guttural and emphatic letters and the [b] sound for bet rafe were retained in many Arab countries, probably under the influence of Arabic.
Iraqi Jews, like Yemenite Jews, retain the Classical Arabic sounds of waw ([w]) and tav raphe ([θ]). In other Arab countries, tav raphe is pronounced [t], which is equally consistent with the pronunciation of both Sephardi Hebrew and of colloquial Arabic. The pronunciation of waw as [v], in countries other than Iraq and Yemen, is more clearly Sephardic in origin.[e]