Definition of analemma in US English:

analemma

noun

Astronomy
  • 1An orthographical projection of the celestial sphere on to the plane of the meridian, the observer being supposed to be at an infinite distance at the east or west point of the horizon. In later use chiefly historical (frequently attributive).

  • 2An instrument or part constructed on the basis of the analemma projection.

  • 3A scale drawn on a terrestrial globe showing the changing position of the true sun over the course of a year; a similar item on a sundial.

  • 4The asymmetrical figure-of-eight curve that can be traced in the sky at a given place showing the position of the sun at mean solar noon on successive days of a year.

Origin

Mid 17th century. From classical Latin analemma diagram showing (for a particular latitude) how the length of the shadow on a sundial varies with the time of year (Vitruvius) from ancient Greek ἀνάλημμα prop or support, in Hellenistic Greek also projection on a plane of circles and points on the celestial sphere from ἀνά- + λῆμμα, after ἀναλαμβάνειν to take up, resume, repair.

Pronunciation

analemma

/ˌanəˈlɛmə/