Contraction of "sham conversation". Used to describe the practice of engaging someone in conversation without aiming to create a rapport or derive any meaningful information from the exchange. Shamversations are occasionally benign but can be of great strategic importance if executed effectively; examples are given below.
"Dude, why don't I engage her friend in a shamversation, then you can have a clear path to score a homerun"
~ as used tactically by a wingman.
"My fucking ex-girlfriend showed up a the club, so I grabbed the first hot chick I could find and started a shamversation."
~ used by a recently dumped guy to avoid social humiliation.
"This weird guy kept messaging me on Facebook, so I'm having a shamversation with him, in case he kills himself or something."
~ used to keep Internet weirdoes at bay.