hypostasis

Short definition from Wiktionary

Noun

1. 1
   A sedimentary deposit, especially in urine.
2. 2
   The essential person, specifically the single person of Christ (as distinguished from his two ‘natures’, human and divine), or of the three ‘persons’ of the Trinity (sharing a single ‘essence’).
3. 3
   The underlying reality or substance of something.
4. 4
   The underlying reality or substance of something: A relationship between a name and a known quantity, as a cultural personification (i.e. objectification with personality) of an entity or quality.
5. 5
   The underlying reality or substance of something: Referring to the hypostatic model of personality; i.e., asserting that humans present themselves in many different aspects or hypostases, depending on the internal and external realities they relate to, including different approaches to the study of personality.
6. 6
   The effect of one gene preventing another from expressing.
7. 7
   Postmortem lividity; livor mortis; suggillation.