Also, thumb a ride. Solicit a free ride, especially by hitchhiking. For example, I've no car; can I hitch a ride home with you? or He was hoping to thumb a ride to the stadium. The verb hitch here alludes to walking unevenly, presumably to hop into a car or truck; raising one's thumb is the traditional signal for stopping a car on the road. [First half of 1900s]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.