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intr.v. hy·per·miled, hy·per·mil·ing, hy·per·miles
To engage in driving practices, such as shifting the transmission to neutral when going down hills, in order to produce the greatest gas mileage possible.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.