The Collaborative International Dictionary of English v.0.48:

Aurora \Au*ro"ra\, n.; pl. E. Auroras, L. (rarely used)
   Auror[ae]. [L. aurora, for ausosa, akin to Gr. ?, ?, dawn,
   Skr. ushas, and E. east.]
   1. The rising light of the morning; the dawn of day; the
      redness of the sky just before the sun rises.
      [1913 Webster]

   2. The rise, dawn, or beginning. --Hawthorne.
      [1913 Webster]

   3. (Class. Myth.) The Roman personification of the dawn of
      day; the goddess of the morning. The poets represented her
      a rising out of the ocean, in a chariot, with rosy fingers
      dropping gentle dew.
      [1913 Webster]

   4. (Bot.) A species of crowfoot. --Johnson.
      [1913 Webster]

   5. The aurora borealis or aurora australis (northern or
      southern lights).
      [1913 Webster]

   Aurora borealis, i. e., northern daybreak; popularly called
      northern lights. A luminous meteoric phenomenon, visible
      only at night, and supposed to be of electrical origin.
      This species of light usually appears in streams,
      ascending toward the zenith from a dusky line or bank, a
      few degrees above the northern horizon; when reaching
      south beyond the zenith, it forms what is called the
      corona, about a spot in the heavens toward which the
      dipping needle points. Occasionally the aurora appears as
      an arch of light across the heavens from east to west.
      Sometimes it assumes a wavy appearance, and the streams of
      light are then called merry dancers. They assume a variety
      of colors, from a pale red or yellow to a deep red or
      blood color. The

   Aurora australisis a corresponding phenomenon in the
      southern hemisphere, the streams of light ascending in the
      same manner from near the southern horizon.
      [1913 Webster]

WordNet (r) 3.0 (2006):

aurora
    n 1: the first light of day; "we got up before dawn"; "they
         talked until morning" [syn: dawn, dawning, morning,
         aurora, first light, daybreak, break of day, break
         of the day, dayspring, sunrise, sunup, cockcrow]
         [ant: sundown, sunset]
    2: an atmospheric phenomenon consisting of bands of light caused
       by charged solar particles following the earth's magnetic
       lines of force
    3: (Roman mythology) goddess of the dawn; counterpart of Greek
       Eos

The Free On-line Dictionary of Computing (19 January 2023):

Aurora

    A Prolog implementation with or-parallelism.

   ["The Aurora Or-Parallel Prolog System", E. Lusk et al, Proc
   3rd Intl Conf on Fifth Generation Comp Systems, pp. 819-830,
   ICOT, A-W 1988].

   (2018-01-01)