Pronounced Sue-un, it is either a= Someone who likes their own posts or status's and no-one comments on them.
B= Someone who spends their life on facebook but only has like 44 friends XD.
Steve= Went to school today XD.
Steve likes this
John, fuck off steve your A Suann.
Jane= oo farmville
Jon= You spend your life on facebook but only have 12 friends, YOU SU-ANN.