Clearly there is a difference of opinion on this. It is a fact many British gardeners have always called their oversized courgettes ‘marrows’. It isn’t surprising as the vegetable marrow (as it was traditionally called) has been an important vegetable on these isles long before the courgette ever made its appearance (or had the courgette been here all along just in the guise of an immature vegetable marrow?).
Vegetable marrows were recorded as early as the 1800s in the UK but it wasn’t until the 1930s that the courgette really started to make an impact here. Courgette is the French name for the small ‘marrow-like fruits’ we shall call them.The Italians call them zucchini and it was the Italian immigrants that took that name to the US, hence why they are more commonly called zucchini there.