originality n.

early 14c., "first in time, earliest," from Old French original "first" (13c.) and directly from Latin originalis, from originem (nominative origo) "beginning, source, birth," from oriri "to rise" (see origin). The first reference is to sin, synne original, "innate depravity of man's nature," supposed to be inherited from Adam in consequence of the Fall (the modern word order original sin is from 15c.). Also from late 14c., "pertaining to or characteristic of the first stage of anything. Meaning "produced directly by an author, artist, etc." is from 1630s; that of "fresh, novel, new, striking" is by 1782. Related: Originally.

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]