The act of scrolling through a social network on one's phone, with loud music of choice playing in the background through a nearby speaker.
An act often performed by a group of multiple people, either in an automobile or basement of a house.
John was 8 mintues late to practice, his daily bump n' scroll in the parking lot took much too long.
"Hey dudes, let's go get high as fuck and bump n' scroll.
Timmy - "Yo Jimbo! Did you notice how many chicks were diggin' my new profile pic?"
Jimbo - "Hell no! I don't evenlook at that troll scroll, and I damn sure don't want to see what Godless ratchet whores are viewing your jacked up pics!"
When you go on a social media site and scroll down for 10 minutes straight, reading every single post that ever existed. Then your scrolling finger goes limp and you can't move it for another 10 minutes.
Hence scroll paralysis.
Quite handy tool for Microsoft Excel. Basically if you have that thing on, you can scroll around the spreadsheet without having to move the selection on a cell.