Ardamírë
From Tolkien Gateway
Ardamir (Q: "Arda-jewel", pron. [ˈardamir], stem Ardamír-) or Ardamírë (pron. [ˌardaˈmiːre]) is the mother-name of Eärendil, son of Idril and Tuor.
Even if the Edain and the Noldor were not lovers of the sea or of ships, Tuor named his son Eärendil, "sea-lover", because Ulmo had foretold him that if he found Gondolin, "he would there beget a son ever afterwards renowned as a mariner". But Idril's choice of mother-name was even more prophetic, for she "could not foresee in her waking mind the strange fate" that led Eärendil to Aman and at last to the skies with the Silmaril on his brow.
References
- J.R.R. Tolkien, Christopher Tolkien (ed.), The Peoples of Middle-earth, "XI. The Shibboleth of Fëanor": The names of Finwë's descendants