An Etymological Dictionary of Astronomy and Astrophysics

1. Sun: A map that displays positions of certain events (e.g., → sunspots, → faculae, → filaments, etc.) observed during one solar rotation.
   

2. Meteorology: The use of data obtained simultaneously over a wide area for the purpose of presenting a comprehensive and nearly instantaneous picture of the state of the atmosphere.

See also: → synoptic; → map.