The definition of a piggyback is a ride on someone's shoulders or back.(noun)
When you throw your arms around someone's neck and are carried on his shoulders and back, this is an example of a piggyback.
To piggyback is to carry or be carried on someone's back, or to use existing work or material as a basis for something you are doing.(verb)
See piggyback in Webster's New World College Dictionary
Origin: alt. of pickaback
See piggyback in American Heritage Dictionary 4
adverb & adj.
Origin: Alteration of dialectal pig back
Origin: , alteration of pickaback, pickback, pick pack
Origin: : probably dialectal pick, to throw (variant of pitch2)
Origin: + back1
Origin: or pack1.
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