Bag의 동의어 A "bag" can be a lot of different things, like a grocery bag, a paper bag, a tool bag, a baseball bag, a ziploc bag, and even a purse is sometimes called a bag. A "pack" is much more specific. It usually refers to a pre-packed container (it could be cloth, plastic, metal) used to hold as many useful items as possible. "Pack" is not a commonly used word. "Bagpack" is not a word. "Backpack" is the correct word it is the specific kind of bag that has shoulder straps, like the kind people take to school or on hikes. A "Backpack" can also be called a bag. Some people call backpacks that are used for school "book bags" or "book sacks." Although, some people hate these words and only call them "backpacks" "Rucksack" is not a common word at all. It is a rough, utilitarian, bag or backpack. "Sack" is used to describe bags that have almost no structure to them. Very loose and floppy bags. The most common use of this word is Sack-lunch (a word to describe a small lunch usually packed in a brown paper bag that i