kleos plural klea: glory, fame (especially as conferred by poetry); that which is heard
kleos is the glory a hero receives after death when he or she is remembered. This remembrance can take many forms: an athletic contest in the hero's honor (and often at the site of the hero's tomb); a religious ritual in which the hero's life is remembered (such as the marriage ritual honoring Hippolytos as described at the end of Euripides' Hippolytos); a continuing line of descendants (as seen in the case of Anchises in the Homeric Hymn to Aphrodite); or, significantly in a song culture such as ancient Greece, through the performance of a song that tells the story of the hero's ordeals, such as the Iliad for Achilles. Achilles is seen performing these types of songs in Scroll 9 of the Iliad when Odysseus, Ajax, and Phoinix come to his tent and find him singer klea andrôn 'the glories of men'.
Achilles actually says in the Iliad that he has a choice between this kind of glory and a long but obscure life. He says to his friends: "My mother tells me that there are two ways in which I may meet my end [telos]. If I stay here and fight, I shall not have a return [nostos] alive but my glory [kleos] will be imperishable ['aphthiton']; whereas if I go home my name [kleos] will perish, but it will be long before the end [telos] shall take me." The adjective aphthiton, "imperishable, unwilting" gives the metaphor for kleos of a flower that never wilts or dies but remains forever fresh and fragrant in full bloom; this metaphor can be extended to a young man like Achilles who dies so prematurely.
These rituals are a form of compensation for the hero's death. Because such a death can never be made up for, the events must recur over and over again, on a seasonal or annual basis. For a modern example of a memorial that incorporates the idea of a seasonal recurring remembrance, compare the St. Gaudens memorial on the Boston Common. This memorial was specifically constructed so that on the Summer Solstice, the faces of the black soldiers, who are not as prominent in the composition as their white officer, are lit up and they are highlighted most of all once a year.
kleos is both the medium (song) and the message (the hero's life). For a connection between music and memory, and how a memory can actually be 're-lived' through music, compare the clip from Bladerunner in which the repliant Rachel, who has no real memories of her own (memories of her creator's niece have been "implanted" in her), recalls having piano lessons. She does not know whether she actually had them, or whether Tyrell's niece did. Yet she can play. With music, whether the experience was her own or someone else's no longer matters: the music itself is real. This is similar to the poet who performs epic poetry and brings the stories to life, claiming that through the Muses he has total recall of everything that happened. Through performance, the singer becomes the person, such as the hero, whose speech he quotes.