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design (on a banner); emblem (on a flag); insignia
banner (e.g. of democracy); slogan; cause; objective
新党は改革を旗印に掲げた。
The new party raised the banner of reform.
武士団は主君の旗印のもと進軍した。
The samurai clan advanced under their lord's insignia.
顧客第一主義を旗印に社員が団結した。
Employees united under the banner of customer-first service.