-ancysuff. Condition or quality: buoyancy.[Latin -antia and -entia; see -ance.]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.-ancy suffix forming nouns a variant of -ance, used to indicate condition or quality: expectancy; poignancy; malignancy. Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014-ancy a combination of -ance and -y, used to form nouns denoting state or quality: brilliancy. [