A map formed by the projection of a sphere or part of a sphere on a plane, especially an adjustable circular star map that shows the appearance of the heavens at a specific time and place.
- ‘Emerging from the whitewashed labyrinth of the Stone Town I found myself looking straight onto a pair of large nineteenth century buildings, both built immediately against the flat blue planisphere of the sea.’
- ‘Out of this flat tropical planisphere rises a series four man-made mountain peaks, each echoed by a ripple of lesser man-made hillocks.’
- ‘Planispheres for now have as north pole the Polaris.’
- ‘Also known as a star wheel, a planisphere is the secret decoder of the sky.’
- ‘On the third floor of the Paris Observatory Cassini had laid out a planisphere, a map of the World using an azimuthal projection with the North Pole at the centre.’
Late Middle English planisperie, from medieval Latin planisphaerium, from Latin planus level + sphaera sphere; later influenced by French planisphère.