Wikipedia
In the works of J. R. R. Tolkien, the fictional Sindar (meaning Grey People, singular Sinda, although the latter term was not generally used by Tolkien) are Elves of Telerin descent. They are also known as the Grey Elves. Their language is Sindarin. The King of Doriath, Elu Thingol (Elwë) was the King of the Sindar.
Usage examples of "sindar".
It was not long before whispered tales began to pass among the Sindar concerning the deeds of the Noldor ere they came to Beleriand.
All the Sindar shall hear my command that they shall neither speak with the tongue of the Noldor nor answer to it.
Elves out of the west-lands, both Noldor and Sindar, Journeyed to Estolad, being eager to see the Edain, whose coming had long been foretold.
Many of the Noldor and the Sindar they took captive and led to Angband, and made them thralls, forcing them to use their skill and their knowledge in the service of Morgoth.
Of the kindred of the Sindar of Nevrast for the most part were those that held this gate.
Of old there was Sauron the Maia, whom the Sindar in Beleriand named Gorthaur.
Sindarin in form and sense, because of the close relationship of the Telerin of Aman to the language of their kin, the Sindar of Beleriand, in spite of the great changes that it had undergone in Middle-earth.
Once upon a time, anyone getting within a parsec of Sindareen space, much less the home world of Sindar, was met with challenges and hostilities .
Then the Sindar received them with joy, and they arose from the darkness of their grief for fallen kin and King and for the departure of Melian.