Definitions by MatanP

Tumblr thumb 

The act of scrolling incessantly through your tumblr pics, usually porn, which produces tumblr thumb: a soreness that comes from long term scrolling on your iPad.

Hey, DuJuan, I'm rolling through the tumblr feed of all the new porn pics on Tumblr. Dude, I've got Tumblr thumb!

Tumblr thumb by MatanP October 10, 2014