One who uses special driving techniques to achieve unusually good fuel economy.(noun)
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Use "hypermiler" in a sentence
"FLACK: Engels is what's known as a hypermiler, a group that takes good gas mileage to extremes."
"On Monday, a team of drivers, including hypermiler Wayne Gerdes and NASCAR driver Carl Edwards successfully completed the 1000 mile challenge, taking a 2010 Ford Fusion Hybrid 1005 miles on less than a single tank of gas."
"Back in January, I wrote a post at Treehugger about the then-current issue of Mother Jones, which included a feature story on “hypermiler” Wayne Gerdes."