from The American Heritage® Dictionary of the English Language, 4th Edition
- suffix State; quality: abnormality.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- suffix Used to form a noun from an adjective; especially, to form the noun referring to the state, property, or quality of conforming to the adjective's description.
- suffix Used to form other nouns, especially abstract nouns.
Middle English -itie, from Old French -ite, from Latin -itās, variant of -tās, -ty.(American Heritage® Dictionary of the English Language, Fourth Edition)
From French -ité, from Middle French -ité, from Old French -ete, -eteit ("-ity"), from Latin -itātem, from -itās, from Proto-Indo-European *-it- (suffix). Cognate with Gothic -𐌹𐌸𐌰 (-iþa, "-th"), Old High German -ida ("-th"), Old English -þo, -þu, -þ ("-th"). More at -th. (Wiktionary)
Nine years later a couple of mathematicians used an equally logical extension of normal, preferring -cy to -ity.
When mocked by users of -ity, the president told his critics to look it up in the dictionary—and there it was, in Merriam-Webster’s.