According to the Glossary of Literary Terms onomatopoeia is “the naming of a thing or action by a vocal imitation of the sound associated with it.” Usually they describe animal noises, machine sounds or acts that make noise. Sometimes they can also express a visually effect like zig-zag.
We can assume that animals all around the world make the same noise- that cow mows the same way in England and in Israel; that clock makes the same clicking sound in North America and Australia. For instance, sound that cat makes is meow in English, miaou in French, miau in German, mjá in Icelandic… But, despite all this there are onomatopoeic words that don’t have the same form across all languages. Here are some examples of different animal sounds for easier overview.
There is a possible explanation for these obvious distinctions. A group of linguists believe that, for instance, various spelling of frog croaking is caused by the fact that different frog species around the world make slightly different sounds. In cooperation with zoologists this group concluded that Aristophanes’ frog sounds brekekekex koax koax might come from the Europe common specie Pelophylax ridibundus also known as the Marsh Frog. On the other hand, Kermit the Frog, who is famous for his ribbit, ribbit sounds on The Muppet Show could belong to Lithobates catesbeianus or the Bull Frog while Michigan J. Frog. from One Froggy Evening based on his lazy croak could be Rana temporaria or the European common frog.
For those of you who want to learn more about onomatopoeic words in different languages here is a list of Cross-linguistic onomatopoeias on Wikipedia.