Being clueless != not knowing the jargon. In fact, one of the most common forms of cluelessness is throwing jargon around in a misguided attempt to show that you know things that you actually don't. Being clueless means not knowing something that you really should have known, and that does not include jargon. I'll give you an example from my own experience: I had a meeting with a name-brand VC during which I levied some harsh criticism at a company that it turned out that they had invested in, indicating that I either didn't know they had invested in it or that I did know and was just being obnoxious. Either way, I was exhibiting cluelessness. One of the many things you are expected to know before talking to any VC is all the information on their web site: their portfolio companies, who the partners are, where they spent their careers, what their investment thesis is. Happily, that one mistake was not enough to actually get me blackballed throughout the industry, but I never had another meeting with anyone at that firm.