backpack

noun

1. a kind of knapsack, often attached to a lightweight frame, worn by campers or hikers
2. a piece of equipment, as a radio transmitter, used while being carried on the back
3. an astronaut's pack used in extravehicular activities to provide a life support system and locomotion
4. a scientific instrument pack attached to people, wild animals, etc. to monitor their physical conditions, locations, etc.

intransitive verb

transitive verb