WordNet sense 1 (an advertisement (usually printed on a page or in a leaflet) intended for wide distribution):

bill, broadsheet, broadside, flier, flyer, handbill, throwaway

WordNet sense 2 (shaped like a ring):

annular, circinate, ringed, annulate, annulated, doughnut-shaped, ring-shaped

WordNet sense 3 (curving and somewhat round in shape rather than jagged):

rounded

WordNet sense 4 (having the shape of a ring):

ringlike

WordNet sense 5 (having a round shape tapered at one end):

pear-shaped

WordNet sense 6 (having a flat circular shape):

discoid, discoidal

WordNet sense 7 (having the shape of a sphere or ball):

orbicular

WordNet sense 8 (having a circular shape):

round

WordNet sense 9 (marked by or moving in a circle):

rotary

WordNet sense 10 (recurring in cycles):

cyclic