Etymology A corruption of pickaback, itself a corruption of pick-pack, like a pack.
1
On somebody's back or shoulders.
give someone a piggyback ride
2
Pertaining to transportation of goods where one transportation unit is carried on the back of something else. For example, a truck on a train.
A Montreal-Toronto "Piggyback" freight of the Canadian Pacific.1959 November, J. N. Westwood, “The Railways of Canada”, in Trains Illustrated, page 554, photo caption:
What might be termed the psychological break-through for U.S. piggyback came in 1953-54. A prototype 75-foot piggyback flatcar was built, establishing the precedent for today's standard car with a capacity for two road trailers.1960 November, David Morgan, “"Piggyback"—U.S. success story”, in Trains Illustrated, pages 681–682:
1 more example
Until this time the railroads had favored piggyback services […]1985, John H. Mahoney, Intermodal Freight Transportation:
3
Attached or appended to something larger or more important.
piggyback legislation
Related terms
TOFC
piggyback
adv
Etymology A corruption of pickaback, itself a corruption of pick-pack, like a pack.
Ambitransitive To attach or append something to another (usually larger) object or event.
They tried to piggyback that proposal on the rivers and harbors bill.
The popular host can’t claim credit for the trade, though. The idea wasn’t his. He piggybacked off another successful investor who had a history of picking winners.
3 more examples
Allen Gregory DeLongpre: Pat, I gotta tell you, you did a lot of things right with this lunch―kudos. You got back quickly, you showed initiative, and, best of all, you left plenty of room for improvement. Piggybacking on that last part, the ugly business of the critique.2011 Allen Gregory, "1 Night in Gottlieb" (season 1, episode 2)
[...] having crossed the river, the District again became entwined with the London & South Western Railway. In fact, the District would go from East Putney to Wimbledon by piggybacking on to a branch line of that railway, and sometimes overground trains still use the branch as a relief route between Wimbledon and Clapham Common.2012, Andrew Martin, Underground Overground: A passenger's history of the Tube, Profile Books, →ISBN, page 81:
But while carrying passengers for recreation is one thing, ferrying bona fide commuters in and out of the UK's third largest city is quite another. Yet that is exactly what Rossendale Borough Council (RBC) wants to do, by piggybacking onto the preserved railway's operations.2023 March 22, Nick Brodrick, “Back to the future on the East Lancs?”, in RAIL, number 979, page 44:
4
Internet To obtain a wireless internet connection by bringing one's own computer within the range of another's wireless connection without that subscriber's permission or knowledge.
5
Internet To utilize "last-mile" wiring rented from a larger owner ISP by a smaller ISP.
6
To transport (a lorry/truck) on a flatbed railway wagon.
American railroads are not permitted to operate long-haul road routes, but the I.C.C. decision of 1954 did permit them to solicit trailer business in, say, New York for Chicago provided the trailer was piggybacked in between.1960 November, David Morgan, “"Piggyback"—U.S. success story”, in Trains Illustrated, page 683:
7
To enter a secured area at the same time along with (someone having authorized access); to tailgate.
Okay, when someone accesses a door with a card key, anyone additional who comes in with them is piggy-backing on their access, like someone riding piggy-back. Get it?
piggyback
noun
Etymology A corruption of pickaback, itself a corruption of pick-pack, like a pack.
1
A ride on somebody's back or shoulders.
2
An act or instance of piggybacking.
The growth is taken for granted; what absorbs Americans today is the implication of piggyback for gross revenues and, more important, net profits.1960 November, David Morgan, “"Piggyback"—U.S. success story”, in Trains Illustrated, page 683:
The GOP had done its homework prior to bargaining for these piggybacks.2000, Craig Allen, Eisenhower and the Mass Media: Peace, Prosperity, and Prime-time TV:
3
Medicine, Sciences The connection of one intravenous drip to another.
Piggyback medications are given through a port of an existing intravenous site. […] Calculation of the drip rate for piggybacks is the same as any other drip rate.1989, Alice J. Smith, Dosage and Solutions Calculations: The Dimensional Analysis Way, page 258:
Certain IV drugs, whether given by piggyback or through a metered-dose infusion set, may be incompatible with an existing continuous IV infusion.2009, Diane S. Aschenbrenner, Samantha J. Venable, Drug Therapy in Nursing, page 34: