After his coronation in J.R.R. Tolkien’s The Lord of the Rings, Aragorn’s royal title is King Elessar.
The name Elessar means “Elfstone” in Quenya, one of Tolkien’s Elvish languages. Aragorn receives the Elessar jewel from Galadriel, and the title connects his kingship with the Elves as well as with the ancient royal line of Númenor. He is crowned after Sauron’s defeat and becomes king of the reunited kingdoms of Arnor and Gondor.
Aragorn is also called Elessar Telcontar. “Telcontar” is a Quenya rendering of “Strider,” the nickname he used while traveling in disguise. These names can cause confusion because Aragorn has several identities across the story: he is Strider among the Rangers, Estel during his youth in Rivendell, and the heir of Isildur by descent. King Elessar is the title associated with his restored public rule, not his earlier wandering life.