What is "quiddities"

Quiddity \Quid"di*ty\, n.; pl. Quiddities. [LL. quidditas, fr. L. quid what, neut. of quis who, akin to E. who: cf. F. quiddit['e].]

1. The essence, nature, or distinctive peculiarity, of a thing; that which answers the question, Quid est? or, What is it? `` The degree of nullity and quiddity.''
   --Bacon.

   The quiddity or characteristic difference of poetry as distinguished from prose.
   --De Quincey.

2. A trifling nicety; a cavil; a quibble.

   We laugh at the quiddities of those writers now.
   --Coleridge.

n. (plural of quiddity English)