You're misreading the chart. It's a histogram of what _names_ people give to a particular color, shown at the bottom of the chart. The regions of color in the

You're misreading the chart. It's a histogram of what _names_ people give to a particular color, shown at the bottom of the chart. The regions of color in the chart are just the weighted average color of the samples that were given that name. The chart does not claim to show what the archetypal hew for any given name is, nor does it try and find the boundary between two colors. This is why in English 'Hot Pink', 'Magenta', and 'Fuchsia' all look about the same ... it's because they're different words for basically the same color. A similar situation is going on with the blue-greens you named. If you look at the slice of the graph for CSS cyan (0% red, 100% green, 100% blue), you'll see that about 20% of respondents called that color "blue", with light blue, cyan, aqua, teal, and turquoise all taking roughly equal amounts of the remainder. Teal, turquoise, and aqua all take approximately equal portions of the same colors, explaining why their representative averages are nearly identical.