Definition of sensible horizon in English:

sensible horizon

noun

  • A circle bounding that part of the earth's surface which is visible from a given point of observation; (also) a circle of the celestial sphere formed by the intersection of the celestial sphere and a plane that passes through a given point of observation.

Origin

Mid 16th century; earliest use found in William Salesbury (d. c1580), translator and humanist scholar.