So 運 is spelled うん, but I seem to hear most of my friends pronounce it as あん. My friends and family are 20-60 years of age and come from mostly Tokyo and Ibaraki area. I am living in the US now and so am not speaking much Japanese, but I remember trying to pronounce it as うん and being misunderstood till I pronounced it as あん (or maybe more like a nasal ahn). Is this a regional dialect? Does anyone pronounce it as うん? Which way should I pronounce it to be understood by most Japanese?