It's such a small word... three little letters: BIG. And yet, it brings to mind all the grandest things in the Universe, from the Big Bang to the Big Mac. In most women's mind the perfect man will need to be big and tall, and although they're basically looking for a secure and peaceful way of life they'll always fall for the big spender... even though throwing money around is hardly a reflection of wisdom and never a good way to ever get that big house to settle in someday.
Same goes in music; there has been many famous trios or orchestras, but only the Big Band rang powerful enough to give its name to a whole era. And in literature; George Orwell could have named his character Overseer or All Powerful Brother... he chose Big Brother instead, and to this day we still fear that he might be watching us.
Over time the very definition of the word has changed to reflect our perception of it. It no longer means merely large or tall, but also impressive, better than average, and sometimes it doesn't refer to size at all. Such can be the power of a word.