The English compound noun cellar door (especially in its British pronunciation) is commonly used as an example of a word or phrase which is beautiful in terms of phonaesthetics (sound) with no regard for semantics (meaning). It has been variously presented either as merely one beautiful instance of many, or as the most beautiful in the English language; either as the author’s personal choice, or that of an eminent scholar, or of a foreigner who does not speak the language. (via werttrew)