Who is Kerth Barker and where did he get his information regarding the definition of Allah? I've looked up the word on two online dictionaries and found this:
Definition of Allah
: GOD sense 1a —used in Islam
Synonyms for Allah
Synonyms
Almighty, Author, Creator, deity, Divinity, Eternal, Everlasting, Father, God, Godhead, Jehovah, King, Lord, Maker, Providence, Supreme Being, Yahweh (also Jahveh or Yahveh)
(source)
Allah
Also found in: Idioms, Encyclopedia, Wikipedia.
Al·lah (ä′lə, ə lä′)
n.
God, especially in Islam.
[Arabic allāh : al-, the + 'ilāh, god; see ʔl in Semitic roots.]
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.
Allah (ˈælə)
n
(Islam) Islam the Muslim name for God; the one Supreme Being
[C16: from Arabic, from al the + Ilāh god; compare Hebrew elōah]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
Al•lah (ˈæl ə, ˈɑ lə)
n. Islam.
the Supreme Being; God.
[< Arabic Allāh]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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Personally, I find the "moon-god" definition a weathered and old tale, and I'm not even Muslim.