Second son of Isildur (S/295), his name seems to be a compound of ar(a)- “noble” and Atan “man”.
Quenya
Aratan
noble adan
aratan
masculine name. *Noble Man
Elements
Word Gloss ar(a)- “noble, high” Atan “Man, (lit.) the Second (People)”
Aratan masc. name *"Noble Adan" (Silm)