backpack

noun

1. A knapsack, sometimes mounted on a light frame, but always supported by straps, worn on a person’s back for the purpose of carrying things, especially when hiking, or on a student's back when carrying books.

   “Rachel discovered that she could also keep things in her backpack that were important to her, nobody would know about them because they would be hidden. These important things included a small round rock that she had found […]”

   “Many seats carry reservation labels, while the luggage racks are festooned with backpacks and suitcases.”

2. A similarly placed item containing a parachute or other life-support equipment.

verb

1. (intransitive)To hike and camp overnight in backcountry with one's gear carried in a backpack.

   “I spent a month backpacking in the Rockies.”

2. (intransitive)To engage in low-cost, generally urban, travel with minimal luggage and frugal accommodation.
3. (rare, transitive)To place or carry (an item or items) in a backpack.

   “Astronauts backpack oxygen during spacewalks.”

   “I planned to go to jungle today and backpacked my things which contained ^([sic]) food and a note book.”