'Swordsman of the Sky' (or Orion), one of the constellations set in the heavens by Varda to enlighten the awakening of the elves and gathered by Varda from among the ancient stars (The Silmarillion, Chap. 3; cf. MR 71, 160). Other constellations were Wilwarin, Telumendil, Soronúmë, Anarríma and Valacirca.
The elements of the Quenya name are: menel 'firmament' and macar 'swordsman'.
MR = Morgoth's Ring (The History of Middle-earth, vol. 10).