trap: [OE] The precise origins of trap are obscure. It goes back to an Old English træppe, and it has various relatives in the modern Germanic and Romance languages – Flemish trape, French trappe, Portuguese trapa, for instance – but its ultimate ancestry has never been unravelled. Its application to a small carriage emerged in the 19th century; it may be short for rattle-trap ‘rickety vehicle’. [trap etymology, trap origin, 英语词源]