Flickr: jillhudgins
Here are how you say meow in different languages although I say how to say meow but for some of them its really how to spell it.
Feel free to add more to the list!
Catalan: “meu”
Chinese: “miao”
Cantonese: “mao”
Danish: “miav”
Dutch: “miauw”
English: “meow”
Finnish: “miau”
French: “miaou”
German: “Miau”
Greek: “naiou”
Hebrew: “Miau” and sometimes “Miya”
Hungarian: “miau”
Japanese: “nyan”, “nya”, “n’yao” or “myah”
Korean: “yaong” or “nyaong”
Norwegian: “mjau”
Portuguese: “miau”
Spanish: “miau”
Swedish: “mjau”
Via: Everything2.com
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Russian: "myuk"