aurora (n.)

Proto-Indo-European root meaning "to shine," especially of the dawn. It forms all or part of: austral; Australia; Austria; Austro-; Aurora; east; Easter; eastern; eo-; Ostrogoth.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit usah "dawn;" Greek ēōs "dawn;" Latin Aurora "goddess of dawn," auster "south wind;" Lithuanian aušra "dawn;" Old English east "east."

1620s, "Northern Lights," literally "northern dawn," said to have been coined by French philosopher Petrus Gassendus (1592-1655) after a spectacular display seen in France Sept. 2, 1621; see aurora + boreal. In northern Scotland and among sailors, sometimes called the dancers, pretty dancers, or merry dancers. Related: Aurora australis (1741).

1550s, "pertaining to dawn," from aurora + -al (1). The meaning "of the color of dawn" is from 1827; the meaning "of the aurora borealis" is from 1828.