I. pig‧gy‧back¹ /ˈpɪɡibæk/ (also ˈpiggyback ˌride) noun [countable]
if you give someone, especially a child, a piggyback, you carry them high on your shoulders, supporting them with your hands under their legs
—piggyback adverb

[TahlilGaran] Dictionary of Contemporary English ▲

II. piggyback² verb [intransitive] informal

1. to use something that is bigger, better, or more successful in order to help another product or project succeed
piggyback on/onto
videos that piggyback onto the success of proven TV programs

2. to use someone else’s wi-fi connection to the Internet, without their knowledge or permission
piggyback on/onto
How can I prevent other people from piggybacking onto my connection?
—piggybacking noun [uncountable]

[TahlilGaran] Dictionary of Contemporary English ▲

piggyback
sitting or being carried on someone's back and shoulders
The boy was riding piggyback on his father's shoulders.

The man was carrying his child around the room piggyback style.

[TahlilGaran] English Idioms Dictionary ▲