You say that an object is floating around when you think it is not far away but you cannot see exactly where.

I can't find my purse, but it must be floating around here somewhere. 我找不到我的钱包了，但是它肯定就在这儿什么地方。

If an idea or story floats around, it is discussed or repeated by a lot of people.

rumours floating around 四处流传的谣言