Ickle Dorritt: Sorry, no idea what a "trifle" is... is it something to eat? It seems like most of the semantic differences are food-related.

Something I always wondered about is this: what is a "vegetable marrow"? In Agatha Christie books, Poirot was always talking about retiring to raise them, and I never knew what they were. I found a picture of one on a webpage, and it looked like a zucchini to me, but someone in this thread said that in the UK zucchinis are called "courgettes", so is a vegetable marrow actually something else? Do we have them in the US by some other name?