1. Truthful; honest.
2. True; real.
[Middle English sothfast, from Old English sōthfæst : sōth, truth; see sooth + fæst, fixed, fast; see fast1.]
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.
2. loyal; true
[from Old English sōthfæst; see sooth, fast1]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
1. based on the truth; true.
2. truthful; veracious.
[before 900; Old English sōthfæst]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.