Yep, my definition is the same. If it is growing where you don't want it, it is a weed. If it is where you want it, it is great.
If Bermuda grass is growing in a hayfield it's hay. If is growing in a lawn, it makes a great lawn grass. If it is in my garden, it's a noxious weed. A vile noxious weed.
There are things I consider a weed no matter where it is, usually because of it's ability to spread and take over. Canadian thistle for example. Due to its ability to seed, take over from native plants, and the damage it does to pastureland and hay fields, I consider it noxious wherever I see it. I know goldfinches like thistle seeds, but darn it,they can eat dandelion seeds.