2BOW stands for Second Banana Of the Week.
What it is is, when they're putting together a movie, and they take a guy (or girl, occasionally) who's known only (or mostly) for a secondary but notable ongoing part in a currently popular TV show, and cast him/her into the movie in a supporting but slightly featured role.
It's characterized particularly by the film part being largely generic, there being no compelling reason for the TV actor to have that particular role, except their agent wants the points, and the producers hope that they can draw a few more butts into seats from the TV actor's fan base.
And it works about 1 % of the time.
In most cases, it's a complete waste of everyone's efforts, except for, I guess, the actor getting paid.
At its best, it's a letdown when the actor's performance is completely devoid of any of the things that he/she is known and liked for doing in the series.
At its worst, it can actually backfire when the actor stinks the joint up.
I always feel like the director has been strong-armed into the casting, against his will, and consequently doesn't do anything to help the 2BOW's performance deliver well.
Bubs in Super, as whatsisname's buddy, could have been played by anyone.
Oh, and 13 from House
Roy from The IT Crowd
in that STUPID STUPID STUPID Jack Black Gulliver's Travels piece of shit, congratulations on taking one of the funniest guys ever on TV and rendering him meaningless, you stupid bastards.
Half Sack from SOA
Actually that one was kind of a twofer, if you count
Harold "WAAAAAAAAAALLLLT!!!!" Perrineau.
Actually that's kind of only a half one, because he was actually in The Matrix 2: Roller Disco Confusion.
Where he got to bang, for the love of Pete, the fuckin delectable
And hey, did she really pork Prince?
How the FUCK does that work?
"Hi, I'm MARVIN FUCKING GAYE'S daughter. I think I need to go bone Prince"
I got no fucking idea, don't ask me.
Oh yeah, a fucking eGREEEgious example (slight variation on a theme here, rather than coming from a Big Hit TV show, the 2BOW comes from a surrpise hit foreign film.)
Another twofer from Slumdog Millionaire, the host dude
(Who wants to be a MILLUNARE? That guy kills me, man) in MI:4.
(And yeah, I know he's a pretty humongous Bollywood star, but this is fuckin Holly wood here.)
And the devastatingly sick-makingly hot
Frieda Pinto in the otherwise excellent New Planet of the Apes.
I'll bet you can think of like 10 right off the top of your head.
Hollywood is SO fucking lame, I swear.