Translation guide
A knapsack is a bag carried on the back, similar to a backpack. In Japanese, the most common equivalent is リュックサック (ryukkusakku), often shortened to リュック (ryukku). Other terms exist for specific types like school bags or mountaineering packs.
A bag carried on the back, used for everyday purposes, travel, or casual outings.
The most common and general term for a backpack or knapsack. Often shortened to リュック in casual speech.
I bought a new knapsack.
I put my lunch in my knapsack.
Shortened, casual form of リュックサック. Very common in everyday conversation.
I went out with my knapsack on my back.
Loanword from English 'backpack'. Used especially for travel or hiking backpacks, but understood generally.
I'm looking for a travel knapsack.
Direct loanword from 'knapsack', but rarely used in modern Japanese. May sound old-fashioned or military.
I found my grandfather's old knapsack.
A specific type of firm, boxy backpack used by Japanese elementary school children.
The traditional hard-sided backpack used by almost all Japanese elementary school students. Not a general knapsack.
I bought a red school knapsack for my daughter.
A large, sturdy backpack designed for mountain climbing or serious hiking.
Although ナップサック is a direct transliteration of 'knapsack', it is rarely used in modern Japanese and may not be understood. Use リュックサック or リュック instead.
Please bring your knapsack.
リュック is the everyday word for any backpack. バックパック often implies a larger travel or hiking pack, but the distinction is not strict. リュック is safer for general use.