look up any word, like ratchet:
 
1.
(Most Common on tumblr.com)

The post-limit is the worst possible thing that could ever happen to the common Tumblr addict. After a user posts what Tumblr finds as "too much" pictures, videos, music, etc. they will reach their Post-Limit. At first, users will usually think, "What?" and after recovering from Post-Limit Shock, they will most likely be angry. A way to bypass this is, have the user go to their settings, and change their timezone to somewhere that is one day ahead of them.
User: Aw shit, I reached my Post-Limit.
by IL0VEYOUALL January 30, 2012
 
2.
Tumblr's way of bringing out Satan.
hipster : im literally going to have a meltdown. i'm on post limit. ugh what even is life.
by perffume February 09, 2013
 
3.
The end of your life.

You can no longer post on Tumblr for the rest of the day/night and you have to wait till 12:00 to start posting again.
Tumblr Person 1: How come you're not posting anymore?

Tumblr Person 2: My life is over untill 12am... post limit ):
by p4cific-blue.tumblr.com June 01, 2012