The actual title is ...

Remember that Classic Star Trek episode about the Greek god Apollo?

The title of that episode is not "Who Mourns for Adonis?" -- despite the fact that you see it rendered that way frequently.

No, the title actually is "Who Mourns for Adonais?" It's a line from the poem "Adonaïs: An Elegy on the Death of John Keats" by Percy Bysshe Shelley; you can read the poem here.

"Adonaïs" is Shelley's own coinage, apparently a blending of the Greek "Adonis" (beautiful young man) and the Hebrew "Adonai" (used in place of YHWH as a name of the God of the Hebrews during prayer recitation).

Now you know. :)

The Robert J. Sawyer Web Site