ára noun "dawn" (AR1). According to VT45:6, ára is also the name of the long vowel carrier of the Tengwar system; it would be the first letter of the word ára if spelt in Tengwar.
Quenya
amaurëa
dawn, early day
amaurëa Archaic
adjective. dawn, early day, morning
ára
dawn
amaurë Reconstructed
noun. dawn, early day, morning
ambarónë
noun. dawn, dawn; [ᴹQ.] uprising, sunrise, Orient
†amaurëa noun "dawn, early day" (Markirya)