What is the name of the primary symbol, which is now outlawed outside of the context of art or science, and was widely used even on the state flag?
Nazi symbolism The 20th century German Nazi Party made extensive use of graphic symbolism, especially the "Hakenkreuz" (swastika), which was used as its principal symbol and, in the form of the swastika flag, became the state flag of Nazi Germany.
Hazard symbol Hazard symbols or "warning symbols" are recognisable symbols designed to warn about hazardous materials, locations, or objects, including electric currents, poisons, and radioactivity. The use of hazard symbols is often regulated by law and directed by standards organisations. Hazard symbols may appear with different colors, backgrounds, borders and supplemental information in order to specify the type of hazard and the level of threat (for example, toxicity classes). Warning symbols are used in many places in lieu of or addition to written warnings as they are quickly recognized (faster than reading a written warning) and more universally understood (the same symbol can be recognized as having the same meaning to speakers of different languages).