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...
By RRELLO
Eugene's tool for carrying his AK-47 while shooting up the local school.
When Eugene reaches into his backpack, you know it's time to run.
By TheCubesAreWarlords
A person who rides your back so hard you need to pry them off. Often a co-worker, teacher or manager in professional settings but could also be a significant other, semi-friend or admirer in social settings.
Rick was tagging along with us at the club last night. He just followed along behind me all night. I'm not taking him out anymore. He's such a backpack! Or, My boss just looms over my desk all day. He's constantly riding me. What a backpack!
By Original Dave
(n) A person that contributes nothing but an overall dour disposition. Typically univited, but tolerated out of a sense of pity.
Dude, that Chris guy is becoming a real backpack! He just shows up and waits for us to entertain his sorry ass.
By Vaness
Hipster rap.
Hey, Joe. Did you hear that new rap song by Lil' Fo'Sheezy? Fuck, no. You non-artistic cunt. Only People who hate music would listen to that mainstream bullshit. I only listen to backpack rap.
By FagginBlagginBloodleDoodle