RAabbr.1. regular army2. residence assistant3. right ascensionRa 1 (rä) also Re (r?)n. Mythology The ancient Egyptian sun god, the supreme deity represented as a man with the head of a falcon crowned with a solar disk and uraeus.[Egyptian r’, sun, Ra.]Ra 2The symbol for radium.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.Ra the chemical symbol for (Elements & Compounds) radium Ra (r??) or Ren (Non-European Myth & Legend) the ancient Egyptian sun god, depicted as a man with a hawk’s head surmounted by a solar disc and serpentRA abbreviation for 1. (Nautical Terms) rear admiral 2. (Astronomy) astronomy right ascension 3. (Art Terms) (in Britain) Royal Academician or Academy 4. (Military) (in Britain) Royal Artillery 5. (Automotive Engineering) Argentina (international car registration) [(sense 5) from República Argentina]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014Ra (r?) also Re n. a sun god of Heliopolis, worshipped throughout ancient Egypt and typically represented as a hawk-headed man crowned with a solar disk and uraeus. RA regular army. Ra Chem. Symbol. radium. R.A. 1. right ascension. 2. royal academician. 3. Royal Academy. Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.RaThe symbol for radium. The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.