Amphinomus

In Greek mythology, Amphinomus, also Amphínomos (Ἀμφίνομος; literally "grazing all about"), was the son of King Nisos and one of the suitors of Penelope that was killed by Odysseus. Amphinomus was considered the best-behaved of the suitors. Despite Odysseus's warning, he was compelled by Athena to stay, as he had been a suitor nonetheless. He was killed by a spear thrown by Telemachus during the murder of the suitors.

Source
He was killed by Telemachus. Refer to page 272 in paperback edition. (Translated by W.H.D. Rouse)
 * Odyssey XVIII, 395, 412; XX, 244; XXII, 89.