Every Saturday I’ll give you a couple of idioms to learn. An idiom is a saying or phrase whose meaning cannot be taken from the literal meanings of the words.
piggyback: sitting or being carried on someone’s back and shoulders
Example:
The toddler became tired due to the long hike, and begged to ride piggyback.
piggy bank: a small bank (sometimes in the shape of a pig) for saving money
Example:
If you really want that bike, you should put at least half your allowance in your piggy bank.