noun
flag of rebellion; standard of revolt
Primarily used in the set phrase 反旗を翻す (はんきをひるがえす), meaning 'to rise in revolt' or 'to rebel'. The noun itself refers to the symbolic banner of an uprising.
See also: 反旗を翻す
彼らは政府に対して反旗を翻した。
They rose in revolt against the government.
反旗を翻す決意を固めた。
They resolved to raise the banner of rebellion.
Compound of 反 (はん, 'anti-', 'rebellion') and 旗 (き, 'flag', 'banner'). The variant 叛旗 uses the character 叛, which also means 'rebel' or 'revolt'.