verb (used without object), hy·per·miled, hy·per·mil·ing
to improve fuel mileage in a motor vehicle, as by adopting certain driving techniques or making design alterations to the vehicle.
Origin of hypermile
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
the practice of maximizing the fuel economy of a motor vehicle, especially through driving technique and vehicle maintenance
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012