That was my definition.

Anything. Everything, All things are things.

If you can use the word 'it', in a sentance to describe it, it is a thing.

Perhaps the simplest definition is: If there is a word, picture or thought that to any degree, greater or lesser, decribes something, then it is a thing.

Returning to the earlier description. If I (or anyone) can conceive of it; it is a thing.

I'm guessing that about now, there are an aweful lot of onlookers wishing this thread would die :)