The word knackered is very commonly used just to mean exhausted. We also use the word knees up, you know, let's have a knees up. The word knob is basically another slang word for a penis. A knob is usually like round or usually if you need to get some socks in your bedroom,. You hold onto it and pull it down with your hand rather than say rudely 'you can't open that' this episode of This Is Life will be on BBC1 at 9pm tonight.