look up any word, like darude - sandstorm:
 
1.
Someone who thinks they know everything but knows nothing.A polite way of calling someone a smartass around proper people or company.
Johnny, you are such a smart one. Or ....Nice going smart one.
by swissmocha April 01, 2005
 
2.
smart one is just a sarcastic way of saying someone is a dumn nut.
"most of my friends are smart ones"...or "man u r such a smart one"
by glonkabletotla June 09, 2009
 
3.
one who lives in their own universe
so smart it scares him,and everyone else.
by bill fry June 18, 2005