How can we know what a thing is without defining it?
By looking at it?
Again, you seem to be looking at it the opposite way than me. It's like if I read somewhere that there's a concept called 'sploffing' that's really wonderful and amazing, I decide I want to do it since it's so wonderful, THEN I go around trying to figure out what it is, trying to find a definition or description for it, and try to find a place where I can truely 'sploff'.
I'd rather look at the world and find things I want to do, places I want to train, etc, and then at some point it might be convenient to slap a label on some of them, maybe. But I like 'aikido' because it's a name commonly used for something I like doing, rather than liking the training because I've decided it's 'aikido'.
If someone came around one day and told me some respected organization or the ghost of Ueshiba or whatever had decreed that what I was doing 'wasn't Aikido', it was really 'Kerplunking', then do you really think that would fundamentally change anything? Well, I'd have to update my family that it's actually called 'Kerplunking'...