fa (fä)n. Music The fourth tone of the diatonic scale in solfeggio.[Middle English, from Medieval Latin; see gamut.]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.fa (f??) n (Music, other) music a variant spelling of fahFA abbreviation for 1. (Military) military field artillery 2. (Soccer) (in Britain) Football Association Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014fa (f?) n. the musical syllable used for the fourth tone of an ascending diatonic scale. [1275?1325; Middle English; see gamut] Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.