bicolour

A bicolour, or bicolor, is something that displays two distinct colours. The term is used across fields to describe patterns, designs, or organisms that feature two contrasting colours, and it is commonly used in the contexts of flags, heraldry, textiles, and biology.

In flags and heraldry, a bicolour refers to a design that uses two solid colours, often arranged in simple fields or bands. Bicolour flags are typically created with horizontal or vertical divisions, and they are among the simplest and most enduring flag designs. Well-known examples include the red-and-white flag of Indonesia, the white-over-red flag of Poland, and the blue-over-yellow flag of Ukraine. In heraldry, “bicolour” can describe a shield or division that presents two tinctures, producing a strong contrast.

Beyond flags, bicolour design appears in textiles, fashion, and printing. A bicolour scheme uses two tones to create visual impact, and it is frequently contrasted with multicolour or polychrome designs. In printing, two-colour or bi-colour printing uses two inks to reproduce imagery or text. The term also extends to biology and botany, where two-coloured organisms or plant parts are described as bicolour, such as certain flowers or animals with two dominant colours.

Etymology derives from bi- meaning two and colour. In usage, the spelling bicolour is common in British English, while bicolor is typical in American English. See also two-tone and bi-colour variants.