Summary

Jakob Jakobsen,  An Etymological Dictionary of the Norn Language in Shetland…

“ The phonology of the Norn words handed down is on the whole somewhat confused, largely owing to the strong Scottish influence, an influence which has made the vowel-system very diversified. In a large number of cases, different forms of a word exist side by side (differing in different districts, but sometimes differing in one and the same district) , frequently representing different stages of development. ”
Source: Wikisource

Jakob Jakobsen,  An Etymological Dictionary of the Norn Language in Shetland…

“ As the i-mutation is so old and so usual a phenomenon in Norse as well as in German, it is almost as a matter of course that it appears in Shetland Norn. There is, however, the peculiarity that the i-mutation is wanting in a great many words in Shetland Norn, in words too, where no closely related words with an original vowel are to be found that could have a smoothing effect and abolish the mutation. ”
Source: Wikisource

Jakob Jakobsen,  An Etymological Dictionary of the Norn Language in Shetland…

“ Whether any u-mutation appears in the Shetlandic word cannot be proved by the vowel-sound.
The u-mutation can be exactly proved in *gøda [gøda, ꬶøda] , sb., way, path, as ø here can only be developed from ǫ in “gǫtu”, nom.: gata. Besides *gøda, the form *goda [gȯda, ꬶȯda] , and (rarely) *gota [ꬶȯta] , is found, and prob. on account of the [ȯ] -sound, must be accepted as a mutated form. “goda, gøda”, now only a place-name, is remembered as a common noun, esp. in Fe. gødins [gødɩns] , in “de Midgødins” (Y.) , is def. pl. form: O.N. gǫturnar, with a later added Eng. pl. s.
”
Source: Wikisource

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