English
horosphere
Horosphere may come from Ancient Greek ὅρος ‘boundary’.
- Ancient Greekc. 800–300 BCEὅροςhóros‘boundary’uncertain
- Englishtodayhorosphere
attested reconstructed ? uncertain or disputed
Earlier history uncertain.
Lineage
- Ancient Greekc. 800–300 BCEὅροςhóros‘boundary’uncertain
- Englishtodayhorosphere
The story
A modern scientific coinage, probably from a Latinized spelling of Ancient Greek ὅρος (hóros, “boundary”) (not to be confused with ὧρος (hôros, “year”), which gave rise to many time-related terms) + -sphere
Linked words
through Ancient Greek ὅρος ‘boundary’
Today it means
noun An n-1-dimensional hyperplane in hyperbolic n-dimensional space: it is (in the Poincaré disk) Euclidean-tangent at infinity to the boundary sphere or (in the upper-half-space model) Euclidean-parallel to the boundary hyperplane.
Language periods are conventional ranges, not dates for this word.
Etymograph / Ancient Greek ὅρος / horosphere