From Longman Dictionary of Contemporary Englishbannerban‧ner /ˈbænə $ -ər/ ●●○ noun [countable] 1 EXPRESSa long piece of cloth on which something is written, often carried between two poles The onlookers were shouting, cheering, and waving banners.2 PPGBELIEVEa belief or principlecarry/raise/wave etc the banner of something (=publicly support a particular belief etc) She’d never felt the need to carry the banner of feminism.under the banner of something They marched under the banner of equal educational opportunity.3 → under the banner of something4 DSa flag
Examples from the Corpus
banner• He was not a brave man, and often said so, brandishing his supposed nervousness like a banner.• A single protester attempted to unfurl a banner in the square on June 3, but was quickly arrested by police.• He is champion of the sceptics, and he sallies forth with his banners flying.• Would we please hang up our sponsor banners so that we were not mistaken for refugees?• Gephardt is the most logical champion to lift that banner.• The protesters were carrying anti-war banners.• On their shelters were slogans flying on red and yellow banners.carry/raise/wave etc the banner of something• In 1418, proclaiming himself the Prince of Pacification, Le Loi raised the banner of revolt.• Some of its leaders fear a revival of left-wing parties waving the banner of social justice.Origin banner (1200-1300) Old French banere 