Originated in West London. Can be used to describe someone who is so shockingly ugly, unimpressive or plain looking that an extreme exclamation is required to describe them. Can be doubled up for emphasis or used to describe something that is so boring it disgusts you.
He's such a dowie bre.
She tried talking to me but she was so dowie i spat in her face.
You're a dowie dowie yatty, go away.
I went to her house on Friday night, it was fucking dowie!