Things of Middle-earth
Meaning: Language of the Grey People
Other Names: Grey-Elven
Description:The most widely used of the Languages of the Elves in Middle-earth.
'The Grey-elven was in origin akin to Quenya; for it was the language of those Eldar who, coming to the shores of Middle-earth, had not passed over the Sea but had lingered on the coasts in the country of Beleriand. There Thingol Greycloak of Doriath was their king, and in the long twilight their tongue had changed with the changefulness of mortal lands and had become far estranged from the speech of the Eldar from beyond the Sea.
The Exiles, dwelling among the more numerous Grey-elves, had adopted the Sindarin for daily use; and hence it was the tongue of all those Elves and Elf-lords that appear in this history. '
RotK, Appendix F, Of the Elves
'The language of the Sindar had changed much, even in unheeded growth as a tree may imperceptibly change its shape: as much maybe as an unwritten mortal tongue might change in five hundred years or more. It was already ere the Rising of the Sun a speech greatly different to the ear from [Quenya], and after that Rising all change was swift, for a while in the second Spring of Arda very swift indeed'
War of the Jewels, The Grey Annals, Excursus on the languages of Beleriand
'The Sindar were also in origin Eldar, and kindred of the Noldor, yet they had never passed the Sea, but had lingered on the shores of Middle-earth. There their speech had changed much with the changefulness of mortal lands in the long Twilight, and it had become far estranged from the high and ancient Quenya. But it was a fair tongue still, well fitted to the forests, the hills, and the shores where it had taken shape.'
Peoples of Middle-earth, Part 1, Ch II, The Appendix on Languages, Commentary
Initially the Númenoreans also spoke Sindarin.
'Though this people used still their own speech, their kings and lords knew and spoke also the Elven tongue, which they had learned in the days of their alliance, and thus they held converse still with the Eldar, whether of Eressëa or of the westlands of Middle-earth'
The Silmarillion, Akallabêth
As the Númenoreans became corrupted Sindarin fell into disfavor, although the Faithful still learned the language. After the Downfall the remaining Númenoreans spoke Sindarin:
'All men of high lineage and all those who were taught to read and write used Sindarin, even as a daily tongue among themselves. In some families, it is said, Sindarin became the native tongue, and the vulgar tongue of Adûnaic was only learned casually as it was needed. The Sindarin was not however taught to aliens, both because it was held a mark of Númenórean descent and because it proved difficult to acquire - far more so than the 'vulgar tongue'
Peoples of Middle-earth, Ch X, 'Of Dwarves and Men', II, The Atani and their Languages
Contributors: Moriel 7.24.03, Lyllyn 7.24.03