(a) verb. When you wanna slack line with the boys and you forget your line.
(b) verb. When you are being very efficient and don’t have the ability to slack off.
(a) Hey Jimmy you ready to tie a line between some trees and bounce n shit?
Nah sorry I forgot my slackline.
Man you’re slackalackin.
(b) Hey Joseph you’ve been working very hard lately it’s almost as if you don’t have the ability to be lazy.
You’re slackalackin Joseph.