The Quenya name of S. Orodreth in some of Tolkien’s later writings (PM/346, 350). It is a compound of the prefixal form arta- of arata “noble” and heru “lord”.
Conceptual Development: His Quenya name was initially Artanáro, but this was changed to Artaresto, while Artanáro became the Quenya name of his son Gil-galad (PM/350). Later, the name was changed again to Artaher and its Sindarin form to S. Arothir, which was probably meant to replace S. Orodreth in The Silmarillion, although Tolkien did not get around to making those changes. The name Artaresto is more compatible with his Sindarin name Orodreth in the published version of The Silmarillion.
Artaher (Artahér-) masc. name "noble lord" (Sindarin Arothir) (PM:346)