The term 'turns green' can be solved by the crossword solution 'DYES'. DYES are substances that are used to impart color to a material, usually fabric or hair. They are often used to make clothing and other items more vibrant and colorful. DYES are also used in food coloring and cosmetics. In the context of the phrase 'turns green', it could refer to a dye that is used to change the color of something from its original color to green.