A colourway is the terminology that Adidas uses to describe the the colour pattern of an Adidas shoe. For example, the Adidas shoes shown below have the following colourways:
Black/White Blue/White Colourway
It is irrelevant what material the Adidas upper is made out of - such as suede, leather, mesh or canvas - the colourway simply refers to the colour the shoe has been dyed in. The colourway usually refers to the colours of the shoes upper - many older Adidas sneakers feature a gumsole which is not painted in any dye - that is usually made from either suede or leather.
Some Adidas uppers - such as the Stan Smith - feature a monotone colourway: plain white. However, most Adidas sneakers feature multiple colours in the colourway - usually two - with the three stripes and the heel patch having a different colour to the rest of the upper; for example: the Adidas Samba (above, left) has a kangaroo leather upper that is dyed in black, and the three stripes, heel patch, and the outersole dyed in white.
Many of Adidas' iconic sneakers - such as the Samba, Stan Smith and LA - have a traditional/standard colourway. Traditionally, the Samba has a black/white colourway, the Stan Smith has a white/green colourway, and the LA has a white/red/navy colourway. However, every Adidas sneaker has been released in multiple colourways; even if the shoe has a traditional colourway. For example, the Samba has been released in a reverse of it's standard colours: a white upper and black stripes/heel patch.
However, many of Adidas' sneakers do not have a standard colourway, but, instead, are released in a vast array of colourways. For example, the Gazelle is released in many colourways: black/white, blue/white, red/white, grey/white, pink/white, green/white, and gold/white. Additionally, popular Adidas sneakers are periodically released in a special edition; typically a special edition sneaker has a different colourway to the standard version of the sneaker.