S. unusual plurals grammar.
In addition to the normal plural patterns from the entry on plural nouns, Sindarin has a number of less common plural patterns resulting from more obscure sound changes.
Plurals with long ó/o from au: Since ancient long ō > ū in Sindarin, a long ó mostly appears in Sindarin words as the result of later phonetic developments: (1) as a lengthening of a short ŏ to overlong ô in monosyllables [whose plurals have ô → ui] and (2) as a reduction of diphthongal au in polysyllables. In the second case, the long ó (< ǭ) resisted i-affection in non-final syllables and did not mutated in plurals:
This is probably part of a general trend whereby long vowels resisted mutation in non-final syllables; ú likewise does not mutate in such circumstances. The long ó from au sometimes further reduced to short o, but it still resisted plural mutation in non-final syllables:
It is conceivable that in cases where au > ó > o appeared in the final syllables of polysyllables, it went through the same mutation as monosyllablic au → oe in plurals. Hence the (archaic?) plural of Balrog (= Bal + raug) would be *Belroeg. I suspect that such plurals would be mostly archaic, and would tend to reform towards normal plural patterns such as *Belryg. However, there are examples like the pseudo-compound Niben-nog “Petty Dwarf (naug)” where the plural is Nibin-noeg, so perhaps the older plural mutation → oe would be retained in more obvious compounds.
Plurals of words with ai in final syllables: Words with the diphthong ai in final syllables (including monosyllables) sometimes remain unmutated in plural forms, but sometimes have plurals with î (or i in polysyllables). In Noldorin from the 1930s, the same is true of the diphthong ei. Compare:
All the mutated plurals share one feature in common: (1) the singular form originally ended in ancient -ya and (2) originally had an i that underwent a-affection to e. In the plural the a-affection did not occur because the ancient final -ā was replaced by plural -ī. Thus:
Conversely, the non-mutating examples originally had -aCya so that a-affection was not a factor:
A similar ai/î variation could arise in the plurals of words ending in ancient -eCya, but in these it was because the plurals underwent i-raising but the singulars did not because the i was not final:
However, the plural variation would not occur in cases where the diphthong ei > ai arose from other phenomenon such as the vocalization of spirants before th, because this vocalization occurs early and (probably) before i-raising:
Hence the plural of taith “mark” (< ✶tektā) is probably unmutated *taith, but the plural of air “lonely” (< ✶eryā) is probably mutated *îr. An attested example of such a plural variation appears in the adjective teleir “of the Teleri” (< ✶teleryā; probably archaic for telair) with plural form telir (PE17/139). It seems these noun classes with either unmutated and mutated plurals were both large enough to survive, and these inconsistencies in Sindarin plurals for words having ai in final syllables are something you simply need to memorize.
Plural mutations after i: Sometimes vowels that follow an i can undergo plural mutations to an i or a y which then absorbs the preceding i. There are a couple of attested examples:
The same would presumably be true of initial i pronounced as “y”; the plural of [N.] iest “wish” is probably *ist. However, this is not true for plural vowel mutations producing results other than i and y, as in Periain plural of Perian “Halfling” and (presumably) *ient plural of iant “bridge”.
Plurals of polysyllables ending in vowels: Most Sindarin words end in a consonant, since short final vowels vanished in Sindarin’s phonetic history. However, in a few cases Sindarin words can end with vowels as the result of other phonetic developments.
Final a from ancient g: In cases where an ancient g > ʒ [ɣ] following another consonant became final after other vowel losses, it developed into a as in:
Of these, only the first has an attested plural form: fili “caves” (NM/304; Ety/PHÉLEG). Thus it seems in these words, the final a became i in plural forms.
Final u from various sources: Final u appears in a number of Sindarin words as the result of various processes, typically after other vowel losses:
There are only a couple of attested plurals for words of this form: cyry plural of curu “skill” (EtyAC/KUR) and ely plural of alw [alu] “wholesome” (PE17/146). Thus it seems in these words, the final u became y in plural forms, the same as its plural mutation in non-final position.
In Noldorin, there are a few of these (archaic) -y plurals in cases where there was an ancient final u that was lost in the singular form:
In all cases the plural was reformed to match normal plural patterns, and there is no sign of this phenomenon in Sindarin. I think these archaic variant plurals can be safely ignored.
Final vowels from lost weak consonants: When a vowel appeared before a weak consonant like h (< s), it might end up being final after other vowel losses. Whether or not this newly-final vowel survived varies. Most of the clear examples are from Noldorin:
In the examples above, the final vowel’s survival probably depends on whether the ancient s was at the end of the primitive word and thus lost early, or whether there was another vowel after s so that s > h > ’ occurred later. In the first case, the newly-final vowel would have been lost along with all other final vowels, but in the second case the h survived long enough to keep the vowel from vanishing, as in bara, hele, tele. Even when the final vowel ultimately vanished, these words would have unusual plurals.
Four of the above words have attested plurals: elei “dreams” (Ety/ÓLOS), peli “fields” (Ety/PEL(ES)), telei “ends” (Ety/TELES), thely “helmets”. The probable phonetic developments of these plurals are:
In all cases, it seems these words would have the (Noldorin or Sindarin) plural mutations that would normally occur in final syllables: -a → -ai (N. -ei), -e → -i, -o/u → -y (N. -ei/-y). In the example of S. thôl with plural thely, Tolkien gave another plural thuil, probably a reformation to the normal plural pattern for ô-monosyllables. Thus, in those cases where the newly-final vowel was also lost, I think there would be a tendency for the word to reform to normal plural patterns. However, in cases where the vowel survived after weak consonant losses, I think the plural mutation would be basically the same as those in final syllables of polysyllables ending in single consonants.
Plurals of monosyllables ending in vowels: There are relatively few Sindarin monosyllabic nouns ending in vowels, but they could result from (extremely rare) Common Eldarin monosyllabic nouns that either ended in a vowel or nouns which became monosyllables after the loss of an ancient weak consonant. Unfortunately, we have very few examples of such nouns, so their possible plural patterns are unclear. The only potential example is fui “paths” a plural of otherwise unattested S. fû (or ?fô).
It is possible the plurals of ancient monosyllables would follow the developments of more ancient diphthongs, so that ai > ae; ei > ī; oi, ui > ui. In the case of ê, ô, û monosyllables, these would be supported by the plural patterns of other words, so that the plurals of [N.] tê “line” is very likely *tî “lines” and l(h)ô “flood” very likely has plural *l(h)ui “floods”. In the case of â, however, any plurals with ae would be incredibly rare (possible non-existent), and I suspect they would reform to ai by analogy with more common monosyllabic plurals resulting from lost weak consonants. A hypothetical example:
Plurals of monosyllables ending in diphthongs: Where a monosyllable ends in a diphthong that resists mutation (ae, oe, ai, ui), it would almost certainly not undergo vowel mutation in its plural. However, any monosyllable ending in u/w-diphthongs might mutate; the three possibilities are -aw, -ew, -iw (since the diphthong ou became either ū or au). Singulars with the diphthong -iw probably do not mutate, but we do have an example of -êw → -îw in Sindarin plurals:
We have no Sindarin plurals of monosyllables ending in -aw, but we do have a fair number of Noldorin examples:
These show the Noldorin-style plural mutation au → ui, and since this mutation became au → oe in Sindarin (N. pl. nuig >> S. pl. noeg “dwarves”), many Neo-Sindarin writers assume -aw → -oe in Sindarin plurals. However, in Noldorin (and Sindarin) the triphthong -uiw reduced to -ui as in N./S. echui(w) “awakening” < ᴹ✶et-kuiwē. In Sindarin, the triphthong -oew seems to survive, as in S. oew “evil deed” or S. lhoew “poison”. Thus it is possible that -aw → -oew in Sindarin plurals:
I personally think the plural mutation -aw → -oew is the most likely result, but it is not attested and thus I think the established Neo-Sindarin practice of -aw → -oe is also acceptable (and certainly easier to pronounce).
Plural suffixes: Sindarin is unusual in that its plural forms are based almost exclusively on vowel mutation. While plurals using vowel mutation are a feature of Welsh, mutational plurals are less common and the Welsh language also uses of a variety of plural suffixes, the most common being “-au”. Indeed, Gnomish of the 1910s used only plural suffixes and no vowel mutations (PE11/10), whereas the Early Noldorin of the 1920s had a mixture of vowel mutations along with a variety of plural suffixes (PE13/123). Only starting with Noldorin of the 1930s did vowel mutation become the norm.
However, plural suffixes are not entirely absent from Sindarin of the 1950s and 60s (and Noldorin of the 1930s and 40s). One of the most common plural suffixes of Gnomish and Early Noldorin was -in, and it continues to appear in some Sindarin (and Noldorin) plurals:
In the case of the plurals elin, [N.] oelin and [N.] ferin, the suffix -in has a clear historical origin, in that the ancient plural suffix -ī preserved an ancient n that was lost in the unprotected singular form, such as:
Plurals like elin may in fact explain the origin of the plural suffix -in, being common enough that the ending was generalized into a plural suffix. Another possible origin is the ancient objective plural suffix -im, but Tolkien said this ancient suffix was lost in Sindarin:
īm survives specifically as a “personal plural” in the form in, in Beleriandic. In {Noldorin >>} Sindarin owing to the loss of final m, n in unaccented final syllables the distinction between subjective and objective plural was lost (PE21/77).
Despite its ambiguous origin, -in does appear in plurals that cannot be justified by historical phonetic developments, such as conin, Drúin, Nauglin plurals of caun, Drû, Naugol. We don’t have enough information to determine when this suffix would or would not be used. It is tempting to say that -in would be used in cases where the mutated plural would be indistinguishable from the singular, but that is not the case with any of our attested examples, where the normal plural mutations would probably produce: coen, Drui, Nogyl (N. Nogeil).
There are a couple Noldorin examples where the vowels before the preserved n are different: terein plural of [N.] †tôr “brother” and therein plural of [N.] †thôr “eagle”; both words are archaic and the latter’s singular was reformed to thoron. However, these examples indicate we might see other “plural suffixes” in Sindarin like -yn that are the result of other plural vowel mutations. There is no indication such suffixes were generalized, and it is unclear whether plural endings like -yn would have survived or instead be reformed in some way.
Singular Suffixes: For some Sindarin and Noldorin words, the plural became the base form and a singular form was derived from it using one of various “singular suffixes”, such as -ig, -eg, -og or -od (the last perhaps Noldorin-only). Examples include:
In the case of glam and l(h)oth, these are collective nouns given a singular form. In the case of gwanún and lhaw, these are fossilized dual nouns given a singular form. In the case of filig (< philikē), it is a plural form indistinguishable from its singular and thus given a singular form (it also had an “analogical singular” fileg reverse engineered from its plural form). Like the plural suffix -in, there are not enough attested examples to deduce any clear rules for when a singular form might be used, but the example filigod gives another way that Sindarin might distinguish singulars from plurals in nouns that do not mutate in their plurals.
Summary: To summarize the above:
Element In