Blue

Color in the visible light spectrum.

Blue blue

Blue is a primary color in the visible light spectrum, typically associated with calmness and serenity. It appears between green and violet in the spectrum.

/bluː/

From Old French bleu, from Proto-Germanic *blēwaz

Blue is a color that reminds you of the sky or ocean, and it's one of the colors we can see with our eyes.

What is blue? It's a color in the visible light spectrum
What causes us to see blue? Objects appear blue when they reflect blue wavelengths of light
Is blue a primary color? Yes, it's considered a primary color in subtractive color mixing

azure cyan sapphire

red yellow green

color

navy blue sky blue royal blue

spectrum rainbow

color perceptual characteristic