What do they mean by "plant"?

Question

sorry if this question sounds stupid...but in BB10 Ollie and Michelle refer to Dan as a "plant"...what does that mean?

Answer 1

They think that he was hired by the producers to stir things up in the show and that he is not a "real" contestant, that auditioned, etc.  They think the photos in his HoH room and his "story" of being a Catholic school teacher and coach are not true.  

For example, if you've seen the reality show "the Mole", the Mole is a player hired by the producers to sabotage the show.  However, in the "the Mole", that's the whole point of the show.  In BB, it's not the point of the show to have a saboteur, although that's kind of what America's Player was .. although, even America's Player was a real contestant, just given secret assignments by the producers.

In reality, of course, Dan is not a plant, just a crazy player, which is why we like watching him!

Answer 2

It means that they think Dan was "planted" in the house as a twist of some kind.  If you are a plant, then it means that you are not an actual player and you did not have to audition.  Michelle and Ollie believed that all Dan's pictures were fakes, and he lied about his occupation, but this isn't true, of course.  They just thought that it was weird how he was able to do some of the things that he did.  I guess they have never seen anyone like him on the show before.  He's just a really good player and has a great strategy.