The common name for nitromethane fuel used in drag racing is Nitro.
Nitromethane is a chemical compound used as the principal fuel in Top Fuel drag racing. In racing conversations, it is commonly shortened to “nitro,” while “nitro fuel” describes the racing mixture more fully. It should not be confused with nitrous oxide, often called “nitrous,” which is an oxidizer supplied separately in some engines.
Nitromethane contains oxygen within its molecule, so an engine can burn much more fuel per cylinder charge than it could with gasoline. Roughly 1.7 kilograms of air are needed to burn 1 kilogram of nitromethane, compared with about 14.7 kilograms of air for gasoline. That allows enormous fuel flow and power, although the fuel also creates extreme stresses and heat.
Top Fuel dragsters generally use nitromethane blended with methanol rather than burning ordinary pump gasoline. The nickname “nitro” is therefore a racing term for the fuel, not a generic name for every performance additive.