backpack

UK: /ˈbækpæk/ US: /ˈbækˌpæk/ ,(bak′pak′)

WordReference Random House Learner's Dictionary of American English © 2026

back•pack /ˈbækˌpæk/  n. [countable]

1. Sport a pack or knapsack carried on one's back.

v. [no obj]

2. Sport to hike using a backpack.

back•pack•er, n. [countable]

WordReference Random House Unabridged Dictionary of American English © 2026

back•pack  (bak′pak′), n. 

1. a pack or knapsack, often of canvas or nylon, to be carried on one's back, sometimes supported on a lightweight metal frame strapped to the body.
2. a piece of equipment designed to be used while being carried on the back.

v.i. 

3. to go on a hike, using a backpack:
   We went backpacking in the Adirondacks.

v.t. 

4. to place or carry in a backpack or on one's back.

• back¹ + pack¹ 1910–15, American.

back′pack′er, n. 

Collins Concise English Dictionary © HarperCollins Publishers::

backpack / ˈbækˌpæk/ noun

1. a rucksack or knapsack
2. a pack carried on the back of an astronaut, containing oxygen cylinders, essential supplies, etc

verb

1. (intransitive) to travel about or go hiking with a backpack