Hallowe'en Moon

This is what the Moon looked like outside my backdoor a few minutes ago. That was about eight hours after the actual full of the Moon, but close enough that, I am told, it is 99.9% illuminated. I bet, like me, you can't tell the difference between this and a fully full Moon.

Some people call this a 'blue moon."

Others like to suggest that's a "wrong" meaning.

Yeah yeah. Ask a thousand people and 999 of them, 99.9%, will likely tell you it is a blue moon.

That's how words get their meaning -- the way most people use them.