“Fall” Or “Autumn” – Which Is Correct? And Why?

“[In the] UK – we call it Autumn, from the French word ‘autompne’, and later, the Latin ‘autumnus’,” begins a now-infamous tweet from 2013. “[In the] US – WE CALL IT FALL BECAUSE LEAF FALL DOWN”. It’s undoubtedly funny, but is it true? Well, not quite….