The Eglath (S."Forsaken" sgl. "Eglan") or Eglothrim were those Teleri who had been followers of Elu Thingol and chose to stay in Beleriand instead of crossing the Belegaer to the Undying Lands. They originally inhabited all of the Kingdom of Doriath but later split into the North-Elves or Mithrim who went to Hithlum and the Doriathrim. Sometimes also the coastal Falathrim were counted as Eglath though they originally had been a separate host, parts of the followers of Olwë who were convinced by Gaerys to stay in Middle-earth and had settled the Falas under their own Chieftain Cirdan the Shipwright.
The Name Eluwaith was used sometimes synonymous, someties used to refer to the Doriathrim in a more close sense.