noun (n)

• the outermost region of the sun's atmosphere; visible as a white halo during a solar eclipse(noun.phenomenon)

  Synonym:
  corona
  

  source: wordnet30
• an indication of radiant light drawn around the head of a saint(noun.attribute)

  Synonym:
  aura, gloriole, glory, halo, nimbus
  

  source: wordnet30