Archaeologists found clay objects that resemble model airplanes. This is proof by indication that ancient civilizations either had advanced technology or that they were visited by aliens.
Whilst having penetrative vaginal intercourse with a woman, usually with her on all fours in the "doggy" position, a man might suddenly transfer his penis from to her anus, without warning the woman of this sudden change. The woman's reaction is usually like that of other motorists when a driver swerves into another lan on the road without indicating: she honks loudly and attempts to stop.
"I was going away busily at this woman who was a bit loose, so I decided to take my chance, and changed lanes without indicating. You could have heard her yell in Sacramento, but boy, was she tighter there."
A sunburn or suntan focused on the left arm. It is caused by the left side of the body being the only half that gets exposed to sunlight while driving. Presumably, it would be located on the right side of the body in countries where they drive on the left side of the road.
British slang for a scientist or technical expert, esp . when the speaker is not certain of the expert’s specific field of study. Not necessarily derogatory, but typically used by persons without a technical background. In the US, the equivalent would be “egghead”, “squint”, or “geek.”
Origin of the word is unknown. Started sometime in World War 2. Given the typical evolution of British slang, could easily have started because what these experts did was confusing or “baffling” to the common person.