What does it mean by "You look like a horse when you laugh down your nose?"? I'm studying English watching Skins 7 but I don't understand the context. Could someone please explain?
To laugh down your nose means to laugh with your mouth shut so that the air that would normally come out your mouth when you laugh is comes out through your nose instead. The air that comes out of your nose makes your nostrils flair up (meaning they become bigger) which makes the person look like a horse as horses tend to have wide nostrils as shown by the image below: