Definitions by RRELLO

Backpack 

Someone who has muscles on their back (naturally or by flexing).

The look of having triceps and biceps on your back muscles.

girl 1: whoooa, check out that hottie!
girl 2: Daaaang gurl, that boy's got a kickass backpack

boy 1: Yo, check out my backpack!
girl 1: sigh, i wish my boyfriend carried a backpack like yours...

Backpack by RRELLO February 18, 2010