Emoticon is not in my dictionary either. Pardon my ignorance, but what does it mean? Another invention?
Neither is "gyrus"- something to do with turning, spinning or spirals? Another invention?
Sorry, I assumed most people using online forums would understand basic net neologisms - or at least be ready to use the web to look things up. Try this:
http://www.google.co.uk/search?q=define%3Aemoticon