Following on this one because my son(4) does something similar, though in his case, I'm not sure that his word choices make sense.
For example, he's always called the signs that tell you not to do something that are a red circle with a line through it "damage" signs. And if he doesn't want something, he might make an x mark with his fingers and say "damage".
The other day, he got upset because I "boosted" him on the stairs. I didn't know what that meant and asked and he explained that it meant I went past him (boosted past him). I suppose this one could come from video games or something, but it was weird.
