-ity
-ity
suff.
State; quality: abnormality.
[Middle English -itie, from Old French -ite, from Latin -itās, variant of -tās, -ty.]
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.
-ity
suffix forming nouns
indicating state or condition: technicality.
[from Old French -ite, from Latin -itās]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
-ty1
, a suffix of numerals that are multiples of ten: twenty; thirty.
[Middle English; Old English -tig, c. Old Frisian -tich, Old High German -zug, Old Norse tigr, Gothic tigjus; akin to ten]
-ty2
, a suffix occurring in loanwords from Latin and French, forming mainly from adjectives nouns denoting state or condition: ability; certainty; chastity; unity.
[Middle English -te(e) < Old French -te(t) < Latin -tātem, acc. of -tās]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.