A term used to mean "see!" in a told you so manner. Usually said in a high pitched voice with intonation. Generally used when something happens that you knew would happen,something typical and often negative- you can then yell "Ian", "Oh Ian, obviously" , "Wiggins","Witchcraft","Waldo"
If your selfish friend steals a large handful of crisps, you can say "Ian!", or if a new band become popular and they all wear trilbies and have curly/long hair and sing in weird voices and wear skinny jeans and pointy shoes or pumps you can say "Ian".
A nublet who tries to appear cool by hanging out with the people he deems to be "cool." Within the group he hangs out with, he usually says little to nothing, smiles and laughs like a child, and says "What?" in an incredulous manner everytime you make fun of him. He is extremely easy to make fun of, having no "backbone" of any sort, and only responds with his classic "What?" expression. You are able to control, manipulate and take whatever you want from him, as he will not fight back or refuse.
The kind of a guy that does not mind if you shit on his chest or face. The guy that will dry hump your leg and leave a cum stain. The kind of guy that will fuck a monkey for fun.
That the definition of an Ian.