Ethanal trimer, also known as trioxane, is a cyclic trimer of the organic compound acetaldehyde. While "ethanal trimer" is the IUPAC name for this compound, there are several other common names that can be used to refer to the same chemical. These include cyclotrioxymethylene, 1,3,5-trioxane, and sym-trioxane. Trioxane is a colorless, crystalline solid that is soluble in water and commonly used as a reagent in organic synthesis. In addition to its applications in chemistry, trioxane is also used as a sterilizing agent and as a fuel in camping stoves and military ration heating devices.