look up any word, like tinder bombing:
 
8.
A crazy person who just cannot control his/her feelings.
Ashley J.K. is a psycho. Whenever someone talk about her she throws down whatever shes holding and screams.
by UrbanAsian2.0 January 05, 2011
 
9.
1. A crazy person or thing. Someone that is Psychotic.

2. An amazing movie made by Alfred Hitchcock from 1960.
1. When my mom found my weed in my underwear drawer she went psycho!

2. I couldn't shower for a week after I watched Psycho!
by AprilIsFreakingAmazingIsh March 14, 2010
 
10.
a deranged and/or psychopathic person who is a mentally ill or unstable person.
the psycho bitch broke my doors with her f***ing head!
by terrific!yo! August 09, 2009
 
11.
A promiscuous woman of questionable mental stability.
"She totally overreacted! What a complete psyc-ho!"
by James Atha February 23, 2008
 
12.
A person who, or organization that, is so obsessed with something that they believe it to be the only right/correct/proper/acceptable thing, believes that their way is never wrong nor does anything wrong, believes all other ways are wrong/evil/misguided/unacceptable and seeks to shove their belief down your throat because they believe you are in need of being educated, converted, saved, etc. They are always close-minded and unable to think for themselves. They simply follow and try to spread whatever screwed-up ideology they were too weak-minded to save themselves from.
That guy's a psycho-patriot.

He's a psycho-american.

They're psycho-christians.

I have psycho-parents.

That's a psycho-religion.

We don't engage in psycho-politics.

Disclaimer: Not all patriots, Americans, Christians, religions or parents are psycho. They were simply used as examples because some of them are psycho.
by Name: Anonymous July 23, 2008
 
13.
A member of the fandom of the tv show psych, which is unfortunately small.

Knows at least 20 Gus nicknames and endings of the phrase "Gus, don't be a..."

Usually ships either Shules, Shassie, Carlowe, or all three.
Psych-o: And then Lassie said-
Friend: Lassie? Like the dog?
Psych-o: you idiot.
by that_psycho August 10, 2013
 
14.
Someone who laughs all alone at something not funny in a Facebook message
"That's really not funny, you're such a psycho"
by bitteraboutthat August 14, 2013