quiddity
noun
Plural: quiddities
The inner nature of something that makes it distinguishable from other things; the essence.
Examples:
—Some erudite experiments?— undertook Mam finally, as Doctor Barton was not returning from his deep mental immersion.
—Believe me, I would like to know the exact quiddity of this too... Friend Kalidon's gift, that's for sure. Sent without a hintiest forehint of explanation. Beyond this, we only have an undateable folktale of challengeable factuality: The last time an oddness like this was mentioned, four people were said to have disappeared. No time to solve one mystery, and another contending case is already creeping in... (Context: Doctor Barton is examining a strange plant his old friend sent him. Nobody can understand what it actually is. Source: J∙ Okram - The Mystery of the Rammed Key.)
Translations:
Slovak / Slovenčina (SK): podstata
Czech / Čeština (CZ): podstata