OS. [j] vanished before [i], [ui]; [{ji|jui}-] > [{i|ui}-]

OS. [j] vanished before [i], [ui]; [{ji|jui}-] > [{i|ui}-]

In (Old) Sindarin it seems [j] vanished before the vowel [i]. A similar sound change occurred in Welsh, where [ı̯] vanished before [i] or [e] (WGCH/§100vi). The vanishing before [e] does not occur in Noldorin or Sindarin, for example: S. eirien “daisy” (SD/126), N. iest “wish” (Ety/YES). There are a number of examples of [j] vanishing before [i], however:

Since the combination [ji] did not occur in Primitive Elvish, this sound change only applied to cases where [i] arose later in (Old) Sindarin, such as when long [ē] became [ī]. There are also a number of Noldorin and Sindarin examples indicating [j] vanished before the diphthong [ui]:

Whether this happened generally before i-diphthongs is unclear; there are not enough examples to be sure. David Salo noted both these changes, and attributed them to Old Sindarin (GS/§4.62, §4.75), but they could have happened later.

Conceptual Development: In Gnomish, the question of [j] sound changes is complicated by the fact that initial [j] usually became [g], as discussed by Roman Rausch in Historical Phonology of Goldogrin (HPG/§2.1). However, as pointed out by Rausch, there are a couple examples of [j] vanishing before [i]:

The second example had a variant form gintha-, so the evidence is ambiguous. Another interesting example is:

Presumably the primitive form of this name was *yelim given the Qenya stem form. This seems to imply that the change of [j-] to [g-] occurred before the limited Gnomish i-affection, so [jelim] > [gelim] > [gilim]. However, in the Qenya Lexicon the root for this word is given as ᴱ√DYELE, indicating a primitive voiced palatal spirant [ʝ] rather than the semi-vowel [j], so perhaps this is the reason for the different phonetic developments. Similarly, the root for ᴱQ. yanta- “to enlarge, increase, add to” is given as ᴱ√DẎṆTṆ in the Qenya Lexicon (QL/106), which could explain Tolkien’s vacillation between gintha- and intha-.

Order (03500)

After 03400 [ē], [ō] became [ī], [ū] ᴹ✶at-yēn-ar > N. edinar Ety/YEN

Phonetic Rule Elements

[ji-] > [i-]
[jui-] > [ui-]

Phonetic Rule Examples

juial > juial jui- > ui- yuy(u)ŋal > S. uial ✧ PE17/169

ON. [j] vanished before [i], [ui]; [ji|jui] > [i|ui]

See OS. [j] vanished before [i], [ui] for discussion.

Order (03200)

After 00700 [ē], [ō] became [ī], [ū] ᴹ✶at-yēn-ar > N. edinar Ety/YEN

Phonetic Rule Elements

[ji] > [i] ✧ PE19/19 (j- > -)
[jui] > [ui]

Phonetic Rule Examples

andjīn > andīn ji > i ᴹ√YEN > N. ennin ✧ Ety/YEN
atjīnar > atīnar ji > i ᴹ✶at-yēn-ar > N. edinar ✧ Ety/YEN
jīn > īn ji > i ᴹ√YEN > N. în ✧ Ety/YEN
jinpanta > inpanta ji > i ᴹ✶yen-panta > ON. inpanta ✧ Ety/YEN
jīnrinde > īnrinde ji > i ᴹ√YEN > iðrind > N. iðrin ✧ Ety/RIN
jīnrinde > īnrinde ji > i ᴹ✶ı̯en-rinde > N. îðrin ✧ Ety/YEN
jīre > īre ji > i ᴹ√YER > N. îr ✧ EtyAC/YER
pantjīnare > pantīnare ji > i ᴹ√KWAT > N. penninar ✧ Ety/YEN
juigal > uigal jui > ui ᴹ√ > N. uial ✧ Ety/KAL
juikal > uikal jui > ui ᴹ√KAL > N. uigâl ✧ EtyAC/KAL
juilu > uilu jui > ui ᴹ√YUL > N. uilw ✧ EtyAC/YUL
juio > uio jui > ui ᴹ√ > N. ui- ✧ Ety/YŪ

G. initial [j] usually became [g]; [j-|ji-] > [g-|i-]

HPG/§2.1

Phonetic Rule Elements

[j-] > [g-]
[ji-] > [i-]

Phonetic Rule Examples

jað > gað j- > g- ᴱ✶ı̯ādh > G. †gath² ✧ GL/37
jaika > gaika j- > g- ᴱ✶yai-ka > G. gaig ✧ GL/43
jaisa > gaisa j- > g- ᴱ✶ı̯aisa > G. gais ✧ GL/37
jakse > gakse j- > g- ᴱ✶ı̯aksĕ > G. gais ✧ GL/37
janta > ganta j- > g- ᴱ√yṇt > G. gant ✧ GL/37
jantā > gantā j- > g- ᴱ√yṇt > G. gantha ✧ GL/37
jata > gata j- > g- ᴱ√yat- > G. gad ✧ GL/36
jata- > gata- j- > g- ᴱ√yat- > G. gada- ✧ GL/36
jatr > gatr j- > g- ᴱ√yat- > G. gadr ✧ GL/36
jatt > gatt j- > g- ᴱ✶yatt- > G. gath¹ ✧ GL/36
jatwa > gatwa j- > g- ᴱ√yat- > G. gadu ✧ GL/36
jav- > gav- j- > g- ᴱ√ı̯aƀa > G. gav- ✧ GL/38
javsta > gavsta j- > g- ᴱ√ı̯aƀa > G. gaust ✧ GL/38
jelim > gelim j- > g- ᴱ√ı̯el > G. Gilim ✧ GL/38
jere > gere j- > g- ᴱ√yĕrĕ(n) > G. ger ✧ GL/38
jōt > gōt j- > g- ᴱ√yat- > G. gôd ✧ GL/36
jōtrā > gōtra j- > g- ᴱ√yat- > G. godra ✧ GL/36
jotta- > gotta- j- > g- ᴱ✶ı̯otta > G. gôtha- ✧ GL/42
juiē > guiē j- > g- ᴱ✶ı̯ōı̯ē > G. gui ✧ GL/42
jinta- > inta- ji- > i- ᴱ√yṇt > G. intha- ✧ GL/37