What is the meaning of Piggybacking?

present participle and gerund of piggyback

The act or process by which someone piggybacks.

2. Riding on someone else's back.

   Riding on someone else's back.

   Transport involving vehicles arranged in an analogous way.

   Inappropriately gaining entry into a restricted area, past a checkpoint, by tagging along behind another person who is authorized.

   Joining in an activity that is initiated or led by someone else.

   Source: wiktionary.org