"state or quality of being contemporaneous," 1772; see contemporaneous + -ity.
Entries linking to contemporaneity
contemporaneous adj.
"living or existing at the same time," 1650s, from Late Latin contemporaneus "contemporary," from the same Latin source as contemporary (adj.)but with an extended form after Late Latin temporaneous "timely." Related: Contemporaneously; contemporaneousness. An earlier adjective was contemporanean(1550s).
-ity
word-forming element making abstract nouns from adjectives and meaning "condition or quality of being ______," from Middle English -ite, from Old French -ete (Modern French -ité) and directly from Latin -itatem (nominative -itas), suffix denoting state or condition, composed of -i- (from the stem or else a connective) + the common abstract suffix -tas (see -ty (2)).
Roughly, the word in -ity usually means the quality of being what the adjective describes, or concretely an instance of the quality, or collectively all the instances; & the word in -ism means the disposition, or collectively all those who feel it. [Fowler]