An attempt to maximize gas mileage by making fuel-conserving adjustments to one’s car and one’s driving techniques; including, keeping the tires properly inflated to maximize gas mileage; removing the roof rack to streamline the car and reduce drag; turning the engine off rather than letting it idle at long stoplights.

Rather than aiming for good mileage or even great mileage, hypermilers seek to push their gas tanks to the limit and achieve hypermileage, exceeding EPA ratings for miles per gallon.

The term hypermiling (high" pur MIGHL ing) is "The Oxford University Press Word of the Year" for 2008.