Dinitrogen oxide is a nitrogen oxide consisting of linear unsymmetrical molecules with formula N2O. While it is the most used gaseous anaesthetic in the world, its major commercial use, due to its solubility under pressure in vegetable fats combined with its non-toxicity in low concentrations, is as an aerosol spray propellant and aerating agent for canisters of 'whipped' cream. It has a role as an inhalation anaesthetic, a NMDA receptor antagonist, a bacterial metabolite, a general anaesthetic, a vasodilator agent, an analgesic, a member of greenhouse gas, a raising agent, a member of food packaging gas, a food propellant and a refrigerant. It is a nitrogen oxide and a gas molecular entity.