Why do we pronounce Dean as /diːn/ but Sean as /ʃɒn/? [duplicate]

pronunciation

The following words which end with an ean are pronounced as /*i:n/ whereas Sean is pronounced as /ʃɒn/:

bean, dean, lean, mean...

Why is Sean not pronounced as /si:n/ but as /ʃɒn/? Where does this irregularity come from? Are there known rules in English for such cases?


Sean is an Irish name, and so follows a completely different set of rules. Siobhan is another Irish name with a very non-English pronunciation.

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