piggybacking
n.— «Sometimes schools will have a student start the lesson by driving another student home, a practice known as “piggybacking.” If there is another student in the car, ask where your teen will be driving and whether the route is suited to his or her abilities.» —“Student drivers get safety checklist” by Tony Bizjak Sacramento Bee (California) Apr. 19, 2008. (source: Double-Tongued Dictionary)
Further reading
How do you pronounce the word route? Does it rhyme with “boot” or “bout”? This is part of a complete episode.
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