Berylline is a rare adjective that describes something as having a blue-green color. Some synonyms for berylline include aquamarine, turquoise, cyan, teal, and seafoam. These words are commonly used to describe the colors of the ocean, tropical landscapes and marine life. Aquamarine is often used to describe the color of gemstones, while cyan and teal are used to describe the color of technology devices. Turquoise is an excellent choice when describing the color of jewelry or clothing. Seafoam applies to the color of the ocean when it's almost white. Choosing the right synonym for berylline can convey the exact shade and tone needed to describe an object, scene or emotion.