Sindarin

Sindarin Phonetic Development (Part 11)

Forums

OS. [ɣ] became [g] before nasals and liquids; [ɣ{mnlr}] > [g{mnlr}]

In the Old Noldorin of the 1930s and 1940s, the voiced velar spirant [ɣ] evolved into [g] before nasals [m] and [n]; the same seems to be true of [ŋ], though Tolkien’s notation is unclear. This development is discussed in Tolkien’s notes on the Feanorian Alphabet from the 1940s:

Sindarin Phonetic Development (Part 10)

Forums

OS. [z] vanished before [d] lengthening preceding vowel; [Vzd] > [V̄d]

In Sindarin and Noldorin, [z] disappeared before the voiced stop [d], modifying the preceding vowel, though the exact phonetic rules evolved between the conceptual stages of the language. For Sindarin, this change is described in a couple places within notes on the Outline of Phonology [OP2] from around 1950:

Sindarin Phonetic Development (Part 9)

Forums

OS. first in pair of voiced stops vocalized; [Vb{bdg}|Vg{bdg}] > [Vu{bdg}|Vi{bdg}]

In Sindarin and Noldorin, the first consonant of a pair of voiced stops became a vowel, but the exact phonetic development evolved between the two conceptual periods. The clearest description of the Sindarin change is in the Outline of Phonology [OP2] from around 1950:

Sindarin Phonetic Development (Part 8)

Forums

OS. [ŋ] vanished except before stop; [ŋ-|VŋV] > [ø-|VøV]

The ancient velar nasal ñ [ŋ] generally vanished in Sindarin and Noldorin, ultimately surviving only in combination with voiced and voiceless stops: [ŋk] and [ŋg], including the larger cluster [ŋgj] (but not [ŋgw] which had already become [mb]). A clear description of this change appears in the second version of Tengwesta Qenderinwa from around 1950:

Sindarin Phonetic Development (Part 5)

Forums

AT. final voiceless stops and [s] vanished in polysyllables; [-SV{ptks}] > [-SVø]

Based on various examples (mainly from Noldorin), primitive polysyllables ending in final voiceless stops (p, t, k) or s lost this final consonant in their phonetic development. Such primitive words were principally derived from KALAT-stems and fairly rare, especially those ending in [p] (PE21/71). Tolkien discussed such words in his notes on Common Eldarin Noun Structure in the late 40s or early 50s:

Sindarin Phonetic Development (Part 3)

Forums

AT. [j] was lost after initial dental; [{ttʰdnl}j-] > [{ttʰdnl}-]

At various points Tolkien indicated that initial palatalized dentals (those with an additional y-sound) lost their palatalization and became simple dentals in the Telerin language family. The clearest description of this change is from a discussion of the development of primitive initial combinations in the Comparative Tables of the 1930s: