Grey (more frequent British English) or gray (more frequent American English) is an intermediate color between black and white. It is a neutral or achromatic color, meaning that it has no chroma and therefore no hue. It is the color of a cloud-covered sky, of ash, and of lead. The first recorded use of grey as a color name in the English language was in 700 CE. Grey is the dominant spelling in European and Commonwealth English, while gray is more common in American English; however, both spellings are valid in both varieties of English.
https://en.wikipedia.org/wiki/Grey