look up any word, like swoll:
 
1.
Unrelenting, someone who never gives up. Ceaseless.

Note: in no way related to a certain Erich who in fact notably fails at persistence.
Erich, being persistent is not your forte. You give in too easily.
by Never Gives Up April 18, 2011
 
2.
Matt H. A person who is very unwilling to fail
"Matt H., If I were to look up persistent in the dictionary I would find your name!"
by Matt Y. H January 16, 2008