The British have some very strange and suggestive expressions often involving sports or body parts. Avoid these.

• ‘Squeaky bum time’.  An exciting part of a process. Comes from the particularly nervous final minutes sports game.
• ‘A total cock-up’. To do something badly. Nothing to do with male poultry. Sounds rude.
• ‘Don’t get your knickers in a twist’.  Kickers are ladies’ underwear. The expression means do not get unnecessarily excited. Usually completely misunderstood.
• ‘That’s a sticky wicket.’ A cricket term meaning difficult circumstances. A wicket refers to an area on the cricket pitch – a sticky wicket is when a soft pitch creates difficult playing conditions. Non-English speakers often think this is some sort of rude sexual expression.
• ‘Gagging for it’. To be very eager to do something. Often has a sexual connotation. Sounds very crude to non-Brits.
• ‘Taking the piss’. Taking liberties at the expense of others. Non-Brits often think it is ‘taking a piss’, a common reference to urinating.
• ‘To pull somebody’s leg’. To tease by telling a lie.
• ‘Tits Up’. When something is broken or has gone wrong. From military slang: ‘Total Inability To Support Usual Performance.’
• ‘Queer the pitch’. To (usually deliberately) spoil other’s chances of success. Originally from market or street traders’ traditions, and in this context, as related to a cricket or football pitch.