A word a person(usually a girl) makes up a word on the spot and then claims its real by luckily finding it on urbandictionary.com or dictionary.com.
Ana:Im gonna exsanguinate you
Lum:You know you cant just make up words
Ana:Its not made up,look it up
Lum:Your damn lucky i tell you
Ana(in secret):Phew,how do i keep guessing these words?