Backpack (noun)

1. A bag with straps that can be worn on the back, used to carry personal items while hiking, traveling, or going to school or work.
2. A bag with straps that can be worn on the back, used to carry personal items while hiking, traveling, or going to school or work.

Origin:

A combination of the word "back" and "pack" meaning a bag that is worn on the back.

Examples:

1. He put his lunch and books in his backpack before leaving for school.
2. She packed a backpack with clothes and supplies for a camping trip.
3. He put his camera and binoculars in his backpack for a hike.
4. She packed a backpack with snacks and water for a day trip.
5. He put his laptop and charger in his backpack for a business trip.