BACKPACK
backpack, back pack, knapsack, packsack, rucksack, haversack
(noun) a bag carried by a strap on your back or shoulder
backpack, pack
(verb) hike with a backpack; “Every summer they are backpacking in the Rockies”
Source: WordNet® 3.1
Etymology
Noun
backpack (plural backpacks)
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.
A similarly placed item containing a parachute or other life-support equipment.
Synonyms
• haversack
• knapsack (US)
• packsack
• rucksack
• bookbag
Verb
backpack (third-person singular simple present backpacks, present participle backpacking, simple past and past participle backpacked)
(intransitive) to hike and camp overnight in backcountry with one's gear carried in a backpack
(intransitive) to engage in low-cost, generally urban, travel with minimal luggage and frugal accommodations
(transitive) to place or carry (an item or items) in a backpack
Source: Wiktionary