aqua for·tis also aq·ua·for·tis (?k?w?-fôr?t?s, ä?kw?-)n. See nitric acid.[New Latin : Latin aqua, water + Latin fortis, strong.]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.aqua fortis (?f??t?s) or aquafortisn (Elements & Compounds) an obsolete name for nitric acid[C17: from Latin, literally: strong water]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014ni?tric ac?id n. a colorless or yellowish, fuming, suffocating, caustic, water-soluble liquid, HNO3, used chiefly in the manufacture of explosives and fertilizers and in organic synthesis. [1790?1800] Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.Aqua fortisNitric acid.1001 Words and Phrases You Never Knew You Didn?t Know by W.R. Runyan Copyright © 2011 by W.R. Runyan