look up any word, like eiffel tower:
 
1.
The more you hate it, the stronger it gets.
Rebecca Black is the epitome of Rule 19.
by flypossums April 30, 2011
 
2.
Used in lifting weights originated from reddit.com:

You cannot criticize anyone's form unless you lift 90%+ of theirs.

The 90%+ extends to Wilks score to help normalize.
Good job - you can barely deadlift 200 and you are talking shit about someone who pulls 600. Rule 19.
by SoloX July 06, 2012
 
3.
A rule created in 1903 by Merrick Gjertson stating that there can only be one girl per internet.
Rule 19, one girl per internet.
by Neb Good May 02, 2007
 
4.
If you dont know it, Google it.
p1: whats a meme?

p2: rule 19, Google it!
by TerrorKingMugen November 28, 2010