medium whack
Medium whack (and other variations) is used to describe something as being whack, but to also to emphasize a lack of interest in the subject. So, it’s essentially the same thing as “whack”, but you add the “medium” part to 1.) Be redundant for no reason and 2.) Indicate feelings of indifference towards the subject, i.e. “It’s whack and I’m already bored of talking about it”.
Example: “How was the bar last night?” “Medium whack, dude. Way too many hipsters dancing to weird music. I should’ve stayed home and watched Netflix.”

Other potential uses…
Medium Funny: “How was ‘The Hangover 2’?”, “I guess it was medium funny.”

Medium Cool: “How was the party in uptown?”, “It was medium cool, I guess…”