What’s the point? Why not write “mom”?
America and Canada are two of the very few countries who spell mum with an “o”. My philosophy is, if the English spell it one way, I’ll say that is correct, since they invented the language.
It is valid British English—but mom is valid American English. It’s correct for British usage (and anyone else who wants to use it) but that doesn’t make mom any less correct either. They’re both correct. Go variety!
Mum Mum Mum Mum Mum and Jonathan are correct, mum is commonly used in Britain and mom is commonly used in America and Canada. Even people in different parts of the U.S. pronounce a myriad of words differently; potato, data, tomato, status, etc. You can’t really complain when people say mum, when you yourself pronounce words differently from other people too.
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