The crossword solution for the term 'Substance for a Juicer' is 'STEROID', which is a seven-letter word. Steroids are a type of organic compound that contain four rings of carbon atoms and are known for their ability to increase muscle mass and strength. They are often used by athletes and bodybuilders to enhance performance, but can also be found in many everyday products such as creams, lotions, and even some juices.