Word Origin & History
c.1420 (implied in orbicular), "sphere, globe," also "emblem of sovereignty," from O.Fr. orbe (13c.), from L. orbem (nom. orbis) "circle, disk, ring," probably related to orbita "wheel track, rut," of unknown origin. Some suggest a connection with the root of orchid (q.v.). A three-dimensional extension
of a word originally describing two-dimensional shapes. Astronomical sense is from 1526, in ref. to the hollow spheres that carried the planets and stars in the Ptolemaic system. Orb weaver spider is first recorded 1889.