The word "spam" is a type of canned meat. It became the term for the act of sending an annoying message many times over the internet after the Monty Python "Spam Sketch" in which every item on the menu contains spam, with the person not liking spam.
According to Dictionary.com, spam is disruptive messages, especially commercial messages posted on a computer network or sent as e-mail. Basically, short, off topic, and just plain annoying posts.
Back on topic, spam is annoying. I hate it when people say "thnks" to walk through's or information steps. That's spam makes me angreh. And the "luv it!" comments are useless and non contributing. Spam, go BAM!
So, actually answering the question: What do you think the word SPAM is?. Just annoying stuff that get's in the skin, that nobody wants to hear or care about.