In heraldry, gules (pronounced with a hard 'g') is the tincture with the colour red, and belongs to the class of dark tinctures called "colours". In engraving, it is sometimes depicted as a region of vertical lines or else marked with gu. as an abbreviation.
The term gules derives from an Old French word goules or gueules meaning "throats" or referring to the mouth of an animal (whence comes the English gullet). The mouth and throat are red, hence the transfer of meaning.
For many decades, heraldic authors have believed that the term may have arisen from the Persian word gul "rose" (coming to Europe via Muslim Spain or brought back by returning Crusaders) , but according to Brault there is no evidence to support this derivation.
In Polish heraldry, gules is the most common tincture of the field. Through the sixteenth century, nearly half of all noble coats of arms in Poland had a field gules with one or more argent charges on them.
The Gules tincture is said to represent the following: