2. Knowingly guessing at a response but speaking with conviction. A combination of Faux (fake) and SME (subject-matter-expert) (Pronunciation: \ˈfō-smē\). It can be used as an adjective or a verb.
Fauxsme: "I bet it took 40 guys at least 3 months to finish this off."
You: "Don't be a fauxsme, you clearly have no idea whatsoever."
If I had to fauxsme this one, I'd bet it took 40 guys at least 4 months to finish this off.