Grey's Anatomy

Grey’s Anatomy Season 10 DVD Extra: The Stars Flunk a Medical Pop Quiz (VIDEO)

It's a good thing the Grey's Anatomy actors sound convincing when they're spitting out medical jargon on the show — because now we're learning that they haven't the foggiest idea what they're talking about.

In the Season 10 DVD extra you see above, the stars of Grey's try defining some of the lingo we've heard 'slung round the halls of Grey Sloan Memorial over the years.

And they bomb the pop quiz — despite the fact that, as James Pickens Jr. (Richard Webber) reveals, they all get cheat sheets of terminology before they film each episode.

"CBC is Cool Boys Club," ventures Jerrika Hinton (Stephanie Edwards). (It's not — it's a complete blood count, a blood panel doctors request for their patients.)

What about a whip stitch? "A stitch," Jessica Capshaw (Arizona Robbins) says. Well, yes, but…

"A whip stitch is when your patient is misbehaving and you have to slap them before you actually go in there and do your business," Jerrika quips.

"Is it the fastest kind of…? I don't know!" laughs Sarah Drew (April Kepner).

Answer? It's a quick suture that doesn't necessitate knots after each stitch.

But you can't blame the actors. They're just focused on the dramatics — not the nitty-gritty details! "Ten years of this," Justin Chambers (Alex Karev) observes. "I'm still struggling to put my gloves on right, so…"

Grey's Anatomy Season 11 premieres Thursday, September 25, at 8 p.m. ET on ABC.