look up any word, like ratchet:
 
1.
title given to someone (preferably male) used to joke and play around with his friends then due to a sudden life change or other circumstances has decided he is officially too grown up for such shenanigans.

n. often found when one enters into the professional world from college or graduate school.
Johnny used to join in on the fun of drinking and playing hilarious pranks with his friends then he got a job in the real world and decided to put aside those "childish" things. He is now referred to by his friends as Mr. Serious.

Pete: you think Johnny will hang out tonight?
Steve: you mean Mr. Serious? I doubt it.
Pete: makes sense. what a douche.
by masterchef22 October 29, 2013
 
2.
title given to someone (preferably male) used to joke and play around with his friends then due to a sudden life change or other circumstances has decided he is officially too grown up for such shenanigans.

n. often found when one enters into the professional world from college or graduate school.
Johnny used to join in on the fun of drinking and playing hilarious pranks with his friends then he got a job in the real world and decided to put aside those "childish" things. He is now referred to by his friends as Mr. Serious.

Pete: you think Johnny will hang out tonight?
Steve: you mean Mr. Serious? I doubt it.
Pete: makes sense. what a douche.
by masterchief69 October 29, 2013