noun (n)

• the first light of day(noun.time)

  Synonym:
  break of day, break of the day, cockcrow, dawn, dawning, daybreak, dayspring, first light, morning, sunrise, sunup
  Antonym:
  sundown, sunset
  

  source: wordnet30
• an atmospheric phenomenon consisting of bands of light caused by charged solar particles following the earth's magnetic lines of force(noun.phenomenon)

  source: wordnet30
• (Roman mythology) goddess of the dawn; counterpart of Greek Eos(noun.person)

  source: wordnet30
• The rising light of the morning; the dawn of day; the redness of the sky just before the sun rises.(noun)

  source: webster1913