Sindarin 

aranuir

masculine name. Aranuir

The 3rd chieftain of the Dúnedain (LotR/1038). The initial element of his name may be aran “king” and its final element might be [N.] uir “eternity” (as suggested by David Salo, GS/341).

Conceptual Development: In the draft of Appendix A of the Lord of the Rings, his name was first given as Aranuil, revised to Aranuir (PM/211).

Sindarin [LotRI/Aranuir; PMI/Aranuir] Group: Eldamo. Published by

Aranuir

noun. eternal king

aran (“king”) + #uir (“eternity”)

Sindarin [Tolkiendil] Group: Tolkiendil Compound Sindarin Names. Published by