Turquoise is a mid-value color blend of blue and green. The term comes from the French for "Turkish". Teal, blue-green, and aqua are similar colors. In holistic medicine, the color turquoise purportedly has a calming effect on patients. In astrology, the color corresponds to the sign of Aquarius. In slang form, the phrase "the Turquoise" refers to the waters of the Caribbean, which are shallow and therefore take on the color in sunlight.