Orange is the colour between red and yellow on the spectrum of light, and in the traditional colour wheel used by painters. Its name is derived from the fruit orange.
In Europe and America, orange is commonly associated with amusement, the unconventional, extroverts, warmth, fire, energy, activity, danger, taste and aroma, the autumn season, and Protestantism. In Asia it is an important symbolic colour of Buddhism and Hinduism.
The colour orange is named after the appearance of the ripe orange fruit. The word comes from the Old French orange, from the old term for the fruit, pomme d'orange. The French word, in turn, comes from the Italian arancia, based on Arabic nāranj, derived from the Sanskrit naranga. The first recorded use of orange as a colour name in English was in 1512, in a will now filed with the Public Record Office.
Before this word was introduced to the English-speaking world, saffron already existed in the English language. Crog also referred to the saffron colour, so that orange was also referred to as ġeolurēad (yellow-red) for reddish orange, or ġeolucrog (yellow-saffron) for yellowish orange. Alternatively orange things were sometimes described as red such as red deer, red hair, the Red Planet and robin redbreast.
In ancient Egypt artists used an orange mineral pigment called realgar for tomb paintings, as well as other uses. It was also used later by Medieval artists for the colouring of manuscripts. Pigments were also made in ancient times from a mineral known as orpiment. Orpiment was an important item of trade in the Roman Empire and was used as a medicine in China although it contains arsenic and is highly toxic. It was also used as a fly poison and to poison arrows. Because of its yellow-orange colour, it was also a favourite with alchemists searching for a way to make gold, both in China and the West.
Before the late 15th century, the colour orange existed in Europe, but without the name; it was simply called yellow-red. Portuguese merchants brought the first orange trees to Europe from Asia in the late 15th and early 16th century, along with the Sanskrit naranga, which gradually became "orange" in English. In parts of Germany, the Netherlands, and Russia, the orange fruit was and is still called the Chinese apple.
read more in https://en.wikipedia.org/wiki/Orange\_(colour)