[1] : The Collaborative International Dictionary of English v.0.48

haecceity \haecce"ity\ he^ks=e"i^ty^, l.
   haecce this. logic
   literally, this-ness. a scholastic term to express
   individuality or singleness; as, this book.
   1913 webster haemato
   haema

[2] : WordNet (r) 2.0

haecceity
     n : the essence that makes something the kind of thing it is and
         makes it different from any other syn: quiddity
see also:
quiddity 

Haecceity >> H Words
Haecceity, definition of term: Haecceity
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