The file voc.txt.gz here was produced from the "Arabic Wordlist for Spellchecking"
version 1.6, downloaded from: https://sourceforge.net/projects/arabic-wordlist/

The commands used to create voc.txt.gz were ("sort -u" used because there's one
duplicate word in the list):

unzip -p Arabic-Wordlist-1.6.zip Arabic-Wordlist-1.6/arabic-wordlist-1.6.txt|sort -u > voc.txt
gzip -9 voc.txt

The "Arabic Wordlist for Spellchecking" is licensed under the GPLv3+:

#-------------------------------------------------------------------------------
# This file is part of Arabic Wordlist for Spellchecking
# 
# Copyright (c) 2013 Mohammed Attia
# 
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
# 
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>
#-------------------------------------------------------------------------------
