Beloved of Aragorn and first queen of reunited Gondor and Arnor (LotR/973). Her name was translated “Noble Maiden” in one of Tolkien’s letters (RC/205). The initial element of her name is the prefix ar(a)- “noble” and its final element is the suffixal form -wen of gwend “maiden”, common in female names.
Conceptual Development: Arwen’s name did not emerge until late in the Lord of the Rings drafts from the 1940s. She was first named N. Ellonel, but this was revised to Finduilas >> Amareth >> Emrahil before Tolkien finally settled on Arwen (SD/66).
ar (prefix “high, noble, royal”) + gwend (“maiden, woman”)