The golden post. Like most arguments I've read (you name it-crossovers, judging, placements, "that team sucked" comments, etc.) it is a matter of perspective. There are so many different situations across the cheer world, her's my attempt to try and get people to agree on a few terms and understand that some will always be subjective and respect that:
"Hit" - an intended skill was accomplished. "Hit a routine", "hit their stunts" or "hit all their tumbling" would be pretty clear
"Clean" - something accomplished had near-perfect technique. Be careful if we start defining this, then we might actually focus on technique as a sport rather than just hitting. That could be dangerous (hope that's obvious sarcasm)
"Killing it" - from your perspective the routine or skill was pretty cool/great/awesome. I think this is a great term for people to use when their team did something right for the first time or has been having trouble. It can also be used to refer to the Rockstar Killers, I suppose. Again, all subjective
"Fierce" - if this term isn't subjective I don't know what is
"Shark-like" - the fiercest! (personally I think this one is pretty clear and should be used more often, but that's just me)
Hope this helps. Seriously, if people take a small effort to understand the other's perspective you might find we actually agree on most things.