One of the constellations devised by Varda to anticipate the awakening of the Elves into the world. Its name apparently contains the word telume, referring to the dome of the sky, so Telumendil means 'friend of the dome of the heavens'.

It is not known for sure which modern constellation corresponds to Telumendil. The similarity of the name to Telumehtar, a name for Orion, is misleading: we can be sure that Telumendil was definitely a distinct pattern of stars. In The Silmarillion, it's named between Wilwarin (modern Cassiopeia) and Soronúmë (probably Aquila, the Eagle). If this order corresponds to the appearance of the constellations in the sky (which is far from certain) then Telumendil would probably correspond to Cygnus the Swan, perhaps viewed as a figure with outstretched arms, as an explanation for the name 'friend of the dome of the heavens'.