Preliminaries
The Yiddish word paze ([‘paz’] in a more accurate transcription) is classified in newer dictionaries as a preposition and glossed with “along” (French “le long de”, German “entlang”, Russian “вдоль”), or less commonly with “by, next to, close to” (French “à côté de”, German “dicht bei”). Its origin has not yet been explained successfully, although both Weinreichs, pere et fils, suggested a borrowing of some Slavonic, but unspecified form: “[…] the (dial[ectal]) preposition paze ‘along’ (of obscure etymology)” (U. Weinreich 1958: 22=390, in the chapter on “Grammatical integration of Slavic-origin words”), “The preposition paze ‘along’ seems to be Slavic-component, but the etymology is not clear” (M. Weinreich 2008, II: A586).
However, not only the etymon of paze turns out to be unclear, but also its exact, in particular original meaning. The word seems rather infrequent in earlier texts, it may even have been dialectally restricted, and its usage can be interpreted in several ways, depending on the actual context.
Yiddish paze in dictionaries
Let us begin with a survey of the major Yiddish lexicographical works. Curiously enough, as a preposition the word in question is absent from all older dictionaries, whether Yiddish-to-something or something-to-Yiddish, and it is only from the second decade of the twentieth century on that paze with this function begins to be recorded. Earlier works have it exclusively as an adverb, or they do not contain it at all, and the meanings later ascribed to this word are by contrast expressed by: in der leng fun and leng-oys (‘along’), or lebn / nebn and ba(y) (‘by, next to’), or the like.
The following reference books have been scrutinized (they are listed here in chronological order of their first edition):
1.1 Neither Lifšicъ (1881) [1869], nor Lifšicъ (1876) records this word.
1.2 Harkavy (1910) [1891/1893] has ‘close to’ paze lebn פאַזע לעבען (p. 79), which indirectly suggests that paze is an adverb here.