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.
strap (strÄp) n. A strip or piece of adhesive plaster. v. strapped, strapÂ·ping, straps To support or bind a part, especially with overlapping strips of adhesive plaster.