adv. & adj.
1. On the shoulders or back: ride piggyback; a piggyback ride.
2. By or relating to a method of transportation in which truck trailers are carried on trains, or cars on specially designed trucks.
3. In connection with something larger or more important: a tariff provision that came piggyback with the tax bill; a piggyback provision to a new piece of legislation.
The act of transporting piggyback.
v. pig·gy·backed, pig·gy·back·ing, pig·gy·backs
To cause to be aligned with an issue, for example, that is larger or more important: "a $21.5-million federal grant to piggyback city and state subsidies" (New York).
To function as if carried on the back of another: "This reagent will piggyback onto an enzyme" (Seth Rolbein).
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.