0 used to show movement into or on a particular place: --
1 used about changing to, or starting to talk about, a different subject: --
3 knowing about someone or something that can be useful to you: --
4 If you are onto someone, you talk to that person, especially to ask them to do something, or to complain to them: --
5 used about someone or something that is added to or joins a particular thing: --
I've managed to offload some of our old furniture onto a friend who's just bought a house.
The president has only held onto power because the opposition is so fragmented.
There was a sudden flare when she threw the petrol onto the fire.