The tying of the bottom of baggy or flared jeans into what looks like a cool 'top' notch hairdo, except it's made of denim and resides towards the 'bottom' of your leg. Can work as a fantastic life and money saver: Buy those cheap unwanted giraffe length jeans, give them a jazzy Bottom Notch, look cool AND avoid tripping up into a motorway/man hole/Bermuda Triangle.
Why use that hair scrunchie for your blonde locks when you can use it to Bottom Notch those hippie jeans instead?