Sean Ruadh, "John the Red," pronounced Shawn Roo.
Tisean (pronounced Tishyán; an as in pan), "envy." Son of King Tisean means "Son of King Envy."
Urféist. This word is made up of Ur and péist. Ur is kindred with the German Ur, and in a compound like this means the "original" or "greatest." Péist—"worm," "beast," "monster"—is changed to féist here, according to a rule of aspiration in Gaelic grammar.
Footnotes
[ 1 ] Loch Léin, former name of one of the Lakes of Killarney.
[2] Lochlin,—Denmark.
[3] The ancient Emania in Ulster.
[4] Shee an Gannon, in Gaelic "Sighe an Gannon," the fairy of the Gannon.
[5] The laughing Gruagach.