Synonyms for Circular:

adj.

all (adjective)
round.
circular (adjective)
cycloid, round, circuitous, rounded, orbital, spherical, annular.
curved (adjective)
rounded.
going around (adjective)
orbicular, ring-shaped, rounded, disklike, round, annular, indirect, circinate, oblique.
round (adjective)
orbicular, spheric, globoid, discoid, spherical, orbiculate, globose, bulbous, globular.
tubular (adjective)
cylindrical.

n.

metaphysical, abstract, conceptual, orthodox, central, utopian, deterministic, popular, theoretical, nonconformist. classified ad, globoid, bumper sticker, banner, banner ad, advert, billboard, advertorial, geometry. revolving, around. unanswered, valid, in black and white, on paper, written, enclosed, returnable, newsy, textual. circuitous (noun)
winding, roundabout, indirect.
circular (noun)
discoid, coccoid, discoidal, broadside, flier, bill, globose, moon-round, flyer, cumuliform, global, round, spheric, cyclical, bulbous, ring-shaped, globular, broadsheet, ball-shaped, handbill, roundish, spherical, capitate, annulate, nutlike, orbicular, pear-shaped, circinate, ringlike, annulated, ringed, cyclic, bulblike, disklike, moonlike, annular, throwaway, orbiculate.
handbill (noun)
flyer, broadside, notice, advertisement, throwaway, publication.
publication (noun)
dissemination, announcement, journalism, broadcast, periodical, propaganda, newspaper, handbill, post, brief, bulletin, promulgation, gazette, journal, advertisement, review, publication, newsmagazine, commercial, promotion, report, newsletter, herald, organ, notice.

Other synonyms:

crosswise, corkscrew, banner, advert, cruciform, unanswered, classified ad, newsy, billboard, banner ad, globoid, elliptical, textual, domed, advertorial, arched, revolving, conical, bumper sticker. hooked, indirect, anfractuous, written. enclosed, oblique, devious, returnable. valid, tortuous, roundabout. around. tubular
cylindrical.

Usage examples for circular

  1. The bridegroom puts a pair of silver rings on the bride's toes and ties the mangal- sutram or flat circular piece of gold round her neck. – The Tribes and Castes of the Central Provinces of India Volume II by R. V. Russell
  2. I reached the first floor, or circular room, and noticed the construction of the window seats- all of rough, solid, and massive stone. – A Bibliographical, Antiquarian and Picturesque Tour in France and Germany, Volume One by Thomas Frognall Dibdin