Color symbolism is the use of color as a representation or meaning of something that is usually specific to a particular culture or society. Context, culture and time are certainly important factors to consider when thinking about color symbolism.
Definition of backpack for English Language Learners. : a bag for carrying things that has two shoulder straps and is carried on the back.
Definition of bag. 1  1 : a usually flexible container that may be closed for holding, storing, or carrying something: such asa : purse; especially : handbagb : a bag for gamec : suitcase.