The word deer is used as a slang term for something being expensive. It can also be used to refer to an older friend or someone you care about. There are other terms of affection that we use when referring to another person, such as 'love'
More informal English for you to pick up in this episode as we continue the series on British slang words. Click the following link to read more information, and the list of slang words I talk about in this episode with some definitions. http://teacherluke.wordpress.com/2013/10/25/150-british-slang-d-to-g (thanks to http://www.effingpot.com/slang.shtml)