threecolored

Threecolored is an adjective used to describe objects or concepts that involve three distinct colors. It is not a formal technical term with a single universal definition; instead its meaning varies by domain.

In graph theory and combinatorics, three-colored is often used to refer to a coloring of a graph's vertices with three colors such that adjacent vertices have different colors. A graph that admits such a coloring is three-colorable; the three-coloring problem asks whether a given graph is three-colorable and is NP-complete for general graphs. Examples include odd cycles, such as triangles, which require at least three colors, while bipartite graphs are two-colorable, and complete graphs on four or more vertices require four colors.

In visual arts, heraldry and flag design, "three-colored" describes schemes using three colors, often in triadic or horizontal/vertical tricolor arrangements. The term is often superseded by "tricolor" in flags; in heraldry, discussions refer to tinctures and color combinations rather than a fixed count.

Because "threecolored" is not a standardized term, writers typically rely on hyphenation "three-colored" or the noun phrase "three colors" or "three-coloring" depending on context.

Related concepts include three-coloring, chromatic number, tricolor, and three-color maps.