The crossword solution for the term RED STREET SIGN is STOP, which is a four letter word. A red street sign is a warning sign that is used to indicate that drivers must STOP their vehicles before proceeding. It is usually placed at intersections or other areas where there is a potential for danger. The sign is typically red in color and has the word 'STOP' written on it in white letters. This sign is an important part of traffic safety and is used to help prevent accidents.