Lyddite was an explosive material used in various weapons during World War I. It was primarily used in artillery shells, bombs, and grenades. However, Lyddite is no longer in use as it has been replaced by modern explosives that are more effective and safer to handle. Some synonyms for Lyddite include picric acid, trinitrophenol, and TNP. Picric acid was one of the original names for Lyddite, while trinitrophenol and TNP are both types of explosive compounds that were similar in chemical composition and explosive power. While all of these synonyms are no longer in common use, they remain important in understanding the history of explosives and weaponry.